PRACTICAL  GAS 
OIL  ENGINE 
HAND  BOOR 

STATIONARY,  MARINE  AND 
PORTABLE  (-AS  AND  GASOLINE 


BROOKES 

UC— NRLr 


GIFT  OF 


THE  PRACTICAL' 

Gas  and  Oil  Engine 
Hand-book 


A  MANUAL  OF  USEFUL  INFORMATION  ON  THE 

CARE,  MAINTENANCE  AND  REPAIR  OF 

GAS  AND  OIL  ENGINES 


By 

JL  ClUott 

AUTHOR  OF  "THE  CONSTRUCTION  OF  A  GASOLINE 

MOTOR,"  AND  "THE  AUTOMOBILE 

HAND-BOOK." 


FREDERICK  J.  DRAKE  &>  CO. 

PUBLISHERS  CHICAGO 


COPYRIGHT,  1905 

BY 

FREDERICK  J.  DRAKE  &  CO. 
CHICAGO 


ft, 

if, 

c! 


PREFACE 

This  work  gives  full  and  clear  instructions  on 
all  points  relating  to  the  care,  maintenance  and 
repair  of  Stationary,  Portable,  Marine  and  Auto- 
mobile, Gas  and  Oil  Engines,  including  How  to 
Start,  How  to  Stop,  How  to  Adjust,  How  to  Re- 
pair, How  to  Test,  and  has  been  written  with  the 
intention  of  furnishing  practical  information 
regarding  gas,  gasoline  and  kerosene  engines, 
for  the  use  of  owners,  operators  and  others  who 
may  be  interested  in  their  construction,  opera- 
tion and  management. 

In  treating  the  various  subjects  it  has  been  the 
endeavor  to  avoid  all  technical  matter  as  far  as 
possible,  and  to  present  the  information  given  in 
a  clear  and  practical  manner. 

-THE  AUTHOR. 


464539 


Gas  and  Oil  Engine  Hand-book 


Actual  Horsepower.  The  expression  actual 
horsepower  is  equivalent  to  brake  horsepower 
and  is  used  to  designate  the  power  which  an 
engine  develops  at  the  driving  pulley. 

The  actual  or  brake  horsepower  of  an  engine 
is  obtained  by  means  of  a  Prony  brake  or  a 
dynamometer  which  gives  the  actual  work  or  per- 
formance of  the  engine  in  foot-pounds  for  any 
given  length  of  time. 

Anti-freezing  Solutions.  To  prevent  freezing 
the  water  in  the  jacket  when  the  engine  is  not  in 
operation  in  cold  weather,  solutions  are  used, 
notably  of  glycerine  and  of  calcium  chloride. 
The  proportions  for  the  former  solution  are  equal 
parts  of  water  and  glycerine,  by  weight,  for  the 
latter,  approximately,  one-half  gallon  of  water  to 
eight  pounds  of  calcium  chloride,  or  a  saturated 
solution  at  60  degrees  Fahrenheit.  This  solution 
is  then  mixed  with  equal  parts  of  water,  gallon 
for  gallon.  Use  the  chemically  pure  salt  only, 
avoiding  the  use  of  the  crude  calcium  chloride  or 
chloride  of  lime. 

Another  solution,  which  is  recommended  by 
other  authorities,  should  consist  of  a  mixture  of 

7 


\8;  :      GAS   AXI«  GIL   ENGINE  HAND-BOOK 

water  and  glycerine,  the  latter  being  about  30  per 
cent  of  the  former  by  weight,  and  adding  to  this 
mixture  two  parts,  by  weight,  of  carbonate  of 
soda.  This  liquid  should  be  entirely  drawn  off 
once  a  month. 

Backfiring.  Its  principal  cause  is  a  prolonged 
combustion  of  the  previous  charge.  When  the 
charge  entering  the  cylinder  does  not  contain  the 
proper  amount  of  fuel  it  makes  a  slow  burning 
mixture.  This  mixture  may  be  so  slow  in  com- 
bustion that  it  continues  to  burn  not  only  during 
the  working  stroke,  but  also  during  the  exhaust 
stroke  of  the  piston,  and  there  still  remains 
enough  flame  in  the  cylinder  to  fire  the  fresh 
charge  being  drawn  into  the  cylinder. 

Any  projecting  point  in  the  valve  chamber  or 
deposits  of  carbon  in  the  cylinder  may  become 
heated  and  serve  to  ignite  the  incoming  charge. 

Regulating  the  fuel  or  air  supply  will  remedy 
the  backfiring  if  caused  by  a  weak  or  a  too 
strong  mixture.  If  this  does  not  remedy  it, 
deposits  of  carbon  or  projecting  points  should  be 
looked  for  and  removed. 

Bearings.  Plain-bearings  are  almost  invari- 
ably used  in  the  construction  of  gas  and  oil 
engines  on  account  of  their  simplicity,  ease  of 
renewal  and  practically  inexpensive  construction. 
Figure  1  shows  a  form  of  crank  shaft  bearing 
much  used  by  the  builders  of  stationary  gas  and 
oil  engines. 


GAS  AND  OIL  ENGINE  HAND-BOOK 


For  plain-bearings,  the  shafts  of  which  are 
continuously  running  at  a  high  rate  of  speed,  the 
working  pressure  per  square  inch  should  not 
exceed  400  pounds.  As  the  arc  of  contact  or 
actual  bearing  surface  of  a  journal-bearing  is 
assumed  as  one-third  of  the  circumference  of  the 
journal  itself,  the  pressure  per  square  inch  upon 
a  bearing  is 
therefore  equal 
to  the  total  load 
upon  the  bear- 
ing, divided  by 
the  product  of 
the  diameter  of 
the  journal  into 
the  length  of  the 
bearing. 

Let  D  be  the 
diameter  of  the 
journal  or  shaft 
at  its  bearing,  and  L  the  length  of  the  bearing, 
if  W  be  the  total  load  or  pressure  upon  the  bear- 
ing and  P  the  pressure  in  pounds  per  square  inch 
of  bearing  surface,  then 


FIG.  1 

Crank-shaft  journal  box  for  gas  or  oil 
engine,  with  wick-feed  oiling  device. 


P  = 


W 


DX  L 


The  crank  shaft  bearings  are  usually  set  at  an 
angle  of  45  degrees,  they  should  be  heavy,  of 
ample  area,  and  readily  adjustable.  Outside 


10       GAS  AND  OIL  ENGINE   HAND-BOOK 

bearings  should  be  fitted  to  large  engines  where 
the  crank  shaft  overhangs.  The  connecting-rod 
bearings  should  be  made  of  phosphor  bronze, 
and  be  made  adjustable  for  wear. 

A  rule  followed  by  some  manufacturers  is  to 
make  the  diameter  of  the  crank  shaft  from  one- 
third  to  one-half  that  of  the  cylinder  diameter. 

Bearings,  Heated.  Heated  bearings  may  arise 
from  a  variety  of  causes,  such  as : 

Bearings  of  insufficient  surface  for  the  load  or 
strain  put  on  them,  engine  running  at  too  short 
centers  with  a  tight  belt,  bad-fitting  or  sprung 
crank  shaft,  bearings  screwed  up  too  tight,  in- 
sufficient lubrication,  improper  or  poor  oil,  dust 
or  dirt  in  the  bearings,  oil  grooves  too  shallow  or 
oil  holes  stopped,  oil  cups  or  lubricators  becom- 
ing air-tight  and  preventing  the  proper  flow  of  oil, 
from  the  engine  being  overloaded. 

Calorific  or  Heat  Values  of  Fuels.  Blast- 
furnace gas  for  operating  large  engines  has  come 
considerably  into  use.  It  is  of  low  calorific 
value,  and  requires  a  high  degree  of  compression, 
but  as  it  is  a  waste  product  in  most  steel  mills  its 
use  will  be  greatly  extended  in  the  near  future. 

The  calorific  value  of  blast-furnace  gas  aver- 
ages about  100  British  thermal  units  per  cubic 
foot,  and  requires  about  1^  times  its  volume  of 
air  for  complete  combustion. 

What  is  known  as  producer  gas  is  now  largely 
used  in  gas  engines,  and  for  large  engines.  When 


GAS  AND  OIL  ENGINE  HAND-BOOK        11 

made  under  favorable  conditions,  undoubtedly  a 
considerable  economy  is  effected,  as  the  cost  is 
usually  only  about  one  cent  per  horsepower,  while 
coal  gas  at  60  cents  per  thousand  feet  would 
amount  to  about  2  cents  per  horsepower. 

Producer  gas  is  usually  made  from  anthracite 
coal  or  coke,  but  a  process  has  been  introduced 
in  which  a  superior  quality  of  gas  is  made  from 
bituminous  coal,  at  the  same  time  a  large 
amount  of  sulphate  of  ammonia  is  obtained  from 
the  fuel,  thus  further  reducing  the  cost  of  the  gas. 

The  calorific  value  of  water  gas  averages  about 
40.0  British  thermal  units  per  cubic  foot. 

The  calorific  value  of  good  coal  gas  is  about 
650  British  thermal  units  per  cubic  foot. 

The  calorific  value  of  producer  gas  is  about 
150  British  thermal  units  per  cubic  foot. 

The  calorific  value  of  gasoline  averages  from 
680  to  710  British  thermal  units  per  cubic  foot 

Gams.  The  proper  form  of  cam  should  give 
an  easy  lift  to  the  valve  and  a  longer  time  for  the 
valve  to  remain  fully  open. 

To  attain  this  object  the 'lift  of  the  valve  and 
consequently  the  throw  of  the  cam  should  be 
about  one-fifth  more  than  is  actually  required 
with  the  ordinary  form  of  cam,  that  is  to  say, 
the  valve  should  lift  more  than  the  amount 
required  for  a  full  opening,  or  this  additional 
amount  of  clearance  should  exist  between  the 
valve  stem  and  the  valve  lifter. 


/ 

/ 

i 


12       GAS  AND  OIL  ENGINE  HAND-BOOK 

As  the  duty  of  a  cam  is  to  transfer  rotary 
motion  of  the  cam  shaft  into  the  necessary  recip- 
rocating action  required  for  lifting  the  valves,  the 
quick  opening  and  closing  of  the  valves  necessary 
in  a  four-cycle  engine  is  more  easily  arrived  at  by 
means  of  a  cam  motion  than  otherwise.  The 
valve  is  closed  by  a  spring,  the  operation  of 
opening  the  valve  being  performed  by  the  cam 
only. 

The  width  of  the  face  of  the  cam  in  contact 
with  the  roller  may  be  ascertained  by  calculating 
the  work  to  be  done  due  to  the  pressure  in  the 
cylinder  at  the  time  of  the  opening  of  the  valve, 
together  Tvith  the  area  of  the  valve.  When  the 
inlet  valve  is  mechanically  operated  the  cam  con- 
trolling its  movement  may  be  of  less  width  than 
the  exhaust  valve  cam,  as  atmospheric  pressure 
only  is  present  when  it  is  in  operation,  as  com- 
pared with  the  exhaust  valve  cam,  which  has  to 
open  the  exhaust  valve  against  a  pressure  some- 
times as  high  as  90  pounds  per  square  inch, 
necessarily  involving  considerable  strain. 

Cam  Shaft  Gearing.  In  the  four-cycle  gas  or 
oil  engine  the  valves  are  only  operated  during 
alternate  revolutions  of  the  crank  shaft.  This, 
therefore,  requires  some  form  of  two-to-one  gear. 
A  form  of  spiral  gear  is  well  adapted  for  this  work. 
The  power  necessary  to  operate  the  valves  is,  in 
this  case,  transmitted  from  the  crank  shaft  by 
the  worm  or  skew  gearing  through  the  cam 


GAS  AND  OIL  ENGINE  HAND-BOOK       13 

shaft,  with  separate  cams  opening  the  inlet  and 
exhaust  valves.  Where  spur  gearing  is  used  the 
cam  shaft  is  mounted  in  bearings  parallel  to  the 
crank  shaft,  the  cams  then  operate  horizontal 
rods  which  open  the  valves. 

Gas  or  oil  engines  having  the  valve  operating 
mechanism  located  near  the  crank  shaft  usually 


FIG.  2 

Spur  and  spiral  gear  types  of  cam-shaft  gearing. 


have  the  spur  form  of  gearing  to  transmit  the 
motion  from  the  crank  shaft  to  the  cam  shaft. 
Engines  having  the  valve  mechanism  adjacent  to 
the  valve  chamber  generally  have  the  spiral  form 
of  gearing  for  the  above  purpose. 

Figure  2  shows  both  forms  of  gearing,  with 
the  spur  gear  drive  the  shafts  are  parallel,  while 


14       GAS  AND  OIL  ENGINE   HAND-BOOK 

with  the  spiral  form  the  shafts  are  at  right  angles 
to  each  other. 

The  left-hand  view  in  the  drawing  shows  the 
spur  gear  drive  and  that  on  the  right  hand  the 
spiral  form  of  gearing. 

Carbureter,  Use  of.  Marine  gasoline  engines, 
requiring  a  greater  range  of  speed  than  is  possible 
with  the  ordinary  forms  of  mixing  valves  or 
vaporizers,  are  usually  equipped  with  a  carbureter 
of  the  float-feed  type. 

The  float-feed  type  of  carbureter  consists  of 
two  principal  parts:  a  gasoline  receptacle  which 
contains  a  hollow  metal  or  a  cork  float,  suitably 
arranged  to  control  the  supply  of  gasoline  from 
the  tank  or  reservoir,  and  a  tube  or  pipe  in  which 
is  located  a  jet  or  nozzle  in  communication  with 
the  gasoline  receptacle,  this  tube  or  pipe  is  called 
the  mixing  chamber.  The  gasoline  level  is  main- 
tained about  one-sixteenth  of  an  inch  below  the 
opening  in  the  jet  in  the  mixing  chamber. 

A  spray  form  of  float-feed  carbureter  is  shown 
in  Figure  3,  it  has  a  gasoline  chamber  A,  float  B, 
needle-valve  stem  C,  gasoline  inlet  D,  regulating 
screw  E,  thumb-piece  F,  lock-nut  G,  spraying 
cone  H,  mixing  tube  J,  jet  or  nozzle  K,  spring  L 
and  plunger  M. 

When  the  gasoline  level  in  the  float  chamber  is 
lowered,  the  needle-valve  stem  falls  with  the 
float,  to  which  it  is  attached,  and  allows  more 
gasoline  to  enter  the  float  chamber  through  the 


GAS   AND  OIL  ENGINE  HAND-BOOK       15 


opening  above  the  needle-valve  stem.  During 
the  suction  stroke  of  the  engine  piston,  air  is 
drawn  into  and  through  the  mixing-chamber,  in 
the  direction  of  the  arrows,  a  small  stream  of 


FIG.  3 

Float-feed  type  of  carbureter,  showing  float-chamber,  mixing- 
tube  and  spray-feed. 

gasoline  is  in  consequence  drawn  up  by  suction 
from  the  jet  or  nozzle,  mixing  with  the  air  in  the 
tube  around  the  spraying  device.  The  carbureter 
may  be  flushed,  for  the  purpose  of  more  readily 


16       GAS  AND  OIL  ENGINE  HAND-BOOK 

starting  the  engine,  by  depressing  the  float  and 
consequently  the  needle- valve  stem,  with  the 
small  plunger  on  the  top  of  the  float-chamber, 
which  is  normally  kept  out  of  contact  with  the 
float  by  a  spring,  as  shown  in  the  drawing. 

Care  of  Gas  or  Oil  Engines,  Directions  for 
the.  Keep  plenty  of  fuel  in  the  tank. 

Water  sometimes  gets  into  the  fuel  tank  and 
when  this  reaches  the  engine  it  begins  to  explode 
irregularly. 

Sometimes  the  water  will  freeze  in  the  fuel 
pipe  and  no  fuel  will  come  through.  In  this 
case,  the  pipes  must  be  thawed  out,  which  may 
be  done  without  disconnecting,  if  the  joints  are 
all  good  and  tight.  There  is  no  danger  in  apply- 
ing heat  to  the  pipes  unless  they  are  leaking. 

Water  in  the  fuel  sometimes  freezes  on  the 
inside  of  the  inlet-pipe. 

By  removing  the  inlet-valve  and  applying  a 
torch  this  can  be  safely  thawed  out. 

The  water  collects  from  condensation  in  the 
tanks  and  otherwise. 

One  cause  of  obstructions  in  the  inlet-pipe  is 
the  use  of  rubber  or  other  soft  gaskets. 

This  should  never  be  done,  as  they  will  soon 
become  loose  and  pieces  get  stuck  in  the  pipe. 
Use  nothing  but  metal  gaskets.  A  ground  joint 
does  not  require  any  packing. 

Always  use  plenty  of  circulating  water. 

Never  allow  the  water  in  the  tank  to  get  lower 


GAS  AND  OIL  ENGINE  HAND-BOOK       17 

than  the  upper  pipe  connection,  as  the  water  can- 
not circulate  unless  this  pipe  is  kept  covered. 

The  lower  water  pipe  and  stopcock  are  liable 
to  become  clogged  up  when  using  dirty  water, 
and  it  is  well  to  see  that  they  are  kept  clean. 

Should  water  passages  between  the  cylinder 
head  and  the  main  water  jacket  become  clogged 
up  they  can  be  cleaned  out  by  removing  the 
cylinder  head  cover  and  scraping  the  passage  with 
an  old  file. 

If  after  an  engine  runs  from  fifteen  to  thirty 
minutes  it  becomes  unusually  warm,  it  is  an  indi- 
cation that  the  water  is  not  circulating  freely. 

If  a  gas  or  oil  engine  is  working  properly,  it 
should  run  smoothly  to  the  ear,  without  pound- 
ing either  in  the  cylinder  or  bearings.  The 
piston  should  work  clean  and  be  well  lubricated, 
without  any  carbon  or  gummy  deposit.  The 
exhaust  gases  at  the  exhaust-pipe  should  be 
invisible  or  nearly  so.  The  explosions  should  be 
regular  and  should  be  only  reduced  in  pressure 
when  the  governor  is  reducing  the  volume  of 
the  charge  and  allowing  only  part  or  none  of 
the  charge  to  enter  the  cylinder. 

Cleaning  a  Gas  or  Oil  Engine.  This  should 
be  regularly  and  thoroughly  performed  at  stated 
intervals,  as  should  the  carbonized  oil  be  allowed 
to  accumulate,  a  great  loss  of  power  may  result. 
The  whole  engine  should  be  taken  to  pieces,  and 
the  cylinder,  piston,  valves,  governors  and 


18       GAS  AND  OIL  ENGINE  HAND-BOOK 


levers  taken   apart  and  thoroughly  cleaned   and 
adjusted. 

To  remove  the  hard  carbonized  oil  from  the 
working  parts  copper  tools  should  be  used,  and 
when  the  parts  are  thoroughly  cleaned  they 
should  be  rubbed  over  with  kerosene.  If  nuts 
are  set  fast  they  should  not  be  forced,  but  be 
loosened  with  kerosene.  By  using  a  little 
powdered  plumbago  and  oil  on  the  screw  threads 
setting  may  be  prevented. 

Combustion  Chamber,  Design  of.  A  simple 
and  exceedingly  practical  construction  for  a  com- 
bustion and  valve-chamber  is  shown  in  Figure  4. 
The  inlet-valve  is  atmospheri- 
cally or  suction  operated,  as 
shown  in  the  drawing.  The 
ignition  plug  is  placed  in  the 
center  of  the  end  of  the  cyl- 
inder, which  is  cast  integral 
or  in  one  piece  and  is  water- 
jacketed  throughout.  The 
combined  combustion  and 
valve-chamber  is  of  funnel 
shape  and  affords  a  straight 
path  for  the  passage  of  the 
gases  without  crooks  or  bends. 
Combustion  Chamber,  Dimensions  of.  If  it 
is  desired  to  ascertain  the  cubic  contents  or 
dimensions  of  the  combustion  chamber  of  an 
existing  engine,  they  may  be  found  by  filling  the 


FIG.  4 


GAS   AND  OIL  ENGINE   HAND-BOOK       19 

combustion  space  with  water,  then  obtaining  the 
weight  of  the  water  in  ounces,  which  multiplied 
by  1.72  will  give  the  capacity  of  the  chamber  in 
cubic  inches.  If  an  engine  is  to  be  designed  with 
a  given  bore  and  stroke,  the  first  thing  to  do  is 
to  decide  on  the  amount  of  clearance  or  combus- 
tion space  at  the  end  of  the  cylinder  for  the  gases 
to  occupy  after  compression. 

If  the  combustion  space  could  be  made  as  a 
continuation  or  extension  of  the  cylinder  bore,  it 
would  be  an  easy  matter  to  determine  the  re- 
quired clearance,  as  it  would  simply  be  some 
fraction  of  the  total  piston  stroke. 

But  as  the  general  design  of  a  combustion 
chamber  deviates  widely  from  a  plain  section  or 
length  of  a  cylinder  as  above  described,  some 
other  method  must  be  used  to  calculate  the 
required  clearance. 

To  do  this  correctly  the  required  contents  of 
the  combustion  chamber  in  cubic  inches  must 
first  be  ascertained,  and  then  apportioned  between 
the  valve  chamber  or  chambers  and  the  clearance 
proper  which  lies  directly  behind  the  piston 
head. 

To  find  the  cubic  contents  of  a  combustion 
chamber  when  the  degree  of  compression  in 
atmospheres  is  known:  Let  S  be  the  stroke  of 
the  piston  in  inches  and  A  the  area  of  the  cylin- 
der in  square  inches.  If  N  be  the  number  of 
atmospheres  compression  and  C  the  required 


20        GAS  AND  OIL  ENGINE  ti^ND-BOOK 

contents  of  the  combustion  in  cubic  inches,  then 

SX  A 
(N-l) 

Example:  Find  the  cubic  contents  of  the 
combustion  chamber  for  a  motor  of  8-inch  bore 
and  10-inch  stroke  with  5  atmospheres  com- 
pression. 

Answer:  Ten  multiplied  by  25.13  equals 
251.3,  which  divided  by  4  gives  62.8  as  the  num- 
ber of  cubic  inches  required. 

Comparison  of  Gas  and  Steam  Engines. 
The  greater  thermal  efficiency  of  the  gas  engine 
as  compared  with  that  of  the  steam  engine  and 
its  adaptability  to  use  the  poorer  and  cheaply 
produced  gases  made  in  producer  plants,  as  well 
as  the  gases  given  off  from  blast  furnaces,  has 
resulted  in  its  development  and  manufacture  in 
units  as  high  as  10,000  horsepower. 

Until  recently  the  gas  engine,  requiring  no  out- 
side gas-making  apparatus,  of  100  horsepower 
was  probably  the  largest  unit  made.  Gas  en- 
gines up  to  500  horsepower  are  now  being  made. 

The  production  of  great  quantities  of  petro- 
leum in  Texas  and  California  chiefly  useful  for 
fuel  purposes  only,  and  which  can  be  procured 
.it  a  low  price  as  compared  with  illuminating  oils, 
has  enabled  the  oil  engine  in  many  locations  to 
compete  in  cost  of  installation  and  price  of  fuel 
with  the  most  economical  types  of  steam  engines. 


GAS  AND  OIL  ENGINE  HAND-BOOK        21 

There  can  be  but  little  doubt  that  large  mod- 
ern gas  engines,  using  a  good  quality  of  producer 
or  blast-furnace  gas  free  from  all  impurities, 
compare  very  favorably  on  the  score  of  economy 
with  the  steam  engine.  This  arises  from  the 
cheapness  of  the  fuel  in  the  first  place,  from  the 
superior  calorific  value  of  gas  over  steam,  and 
the  more  efficient  utilization  of  the  heat  in  the 
gas  engine. 

Comparison  of  Horizontal  and  Vertical  En- 
gines. Accessibility  of  the  parts  in  a  horizontal 
engine  is  always  considered  a  great  advantage. 
The  piston  can  always  be  seen  and  can  be  taken 
out  of  the  cylinder  and  cleaned  and  replaced 
easily  in  this  style  of  engine,  while  in  a  vertical 
engine  it  is  necessary  to  remove  the  cylinder 
cover  and  sometimes  the  cylinder  to  gain  access 
to  the  piston,  and  it  is  also  necessary  to  have 
sufficient  room  above  the  top  of  the  cylinder  to 
lift  the  piston  and  connecting-rod  out.  The  con- 
necting-rod is  more  accessible  for  adjustment 
both  at  the  crank-pin  end  and  at  the  piston  end 
in  the  horizontal  type.  This  difficulty,  however, 
has  been  overcome  by  arranging  a  removable 
plug  in  the  piston  head,  which  when  taken  out 
allows  access  to  the  piston  end  of  the  connecting- 
rod. 

Vertical  engines  for  places  where  space  is  re- 
stricted and  where  sufficient  head  room  is  avail- 
able have  the  greater  advantage  of  occupying  less 


22       GAS  AND  OIL  ENGINE  HAND-BOOK 

floor  space  than  a  horizontal  engine.  The 
mechanical  efficiency  of  a  vertical  engine  is,  how- 
ever, somewhat  greater,  the  friction  of  the  piston 
being  less  than  in  the  horizontal  type  of  engine. 

Sometimes  the  vertical  type  of  engine  can 
only  be  used,  but  for  ordinary  uses  the  horizontal 
type  of  engine  seems  to  be  most  in  favor,  one 
important  point  being  the  difficulty  of  suitably 
arranging  the  carbureting  or  vaporizing  devices 
in  the  vertical  type  of  engine,  which  are  usually 
placed  close  to  the  cylinder,  and  are  not  so  fully 
under  the  control  of  the  attendant  as  in  the  hori- 
zontal engine. 

Comparison  of  Two  and  Four-cycle  Gas 
Engines.  The  trend  in  design  of  large-size  gas 
engines  using  producer  or  blast-furnace  gas  is  to 
the  two-cycle  principle  of  operation.  Where  the 
four-cycle  principle  is  adhered  to,  two  or  more 
cylinders  are  necessary.  As  the  four-cycle  single- 
cylinder  engine  obtains  an  impulse  only  once 
in  two  revolutions,  consequently  during  three 
idle  strokes  of  the  piston  the  power  and  speed  of 
the  engine  must  be  maintained  by  the  momentum 
of  the  flywheels,  necessarily  enormous  in  an 
engine  of  500  horsepower  or  over,  for  the  power 
obtained,  in  comparison  with  the  flywheel  of  a 
steam  engine  of  the  same  capacity.  With  the 
two-cycle  engine  of  large  horsepower,  in  which 
an  impulse  is  obtained  each  revolution  of  the 
crank  shaft,  nearly  double  the  power  is  said  to 


GAS  AND  OIL  ENGINE  HAND-BOOK       23 

be  developed  as  compared  with  the  four-cycle 
engine  of  the  same  size.  The  mechanical 
efficiency  is  increased,  owing  to  the  reduced 
weight  of  the  flywheels,  and  the  weight  and  cost 
of  the  engine  per  horsepower  is  reduced. 

The  difficulty  of  procuring  proper  combustion 
in  the  two-cycle  oil  engine,  where  crude  oil  is 
used,  has,  however,  not  yet  been  entirely  over- 
come. 

It  may  be  stated  that  the  larger  size  two-cycle 
engines,  to  compete  with  the  four-cycle  gas 
engine  in  cost  of  fuel,  can  do  so  only  when  a 
cheap  grade  of  fuel  is  used.  To  use  such  fuel, 
it  is  imperative  that  proper  combustion  should 
take  place  in  the  cylinder. 

Compressed  Air  Starters.  On  account  of  the 
difficulty  of  starting  large  engines  by  hand,  self- 
starters  are  used  for  engines  over  10  to  12  horse- 
power, and  a  great  variety  of  methods  are  in  use. 
Compressed-air  starters  are  simple  and  consist 
usually  of  a  hand  or  power  air  pump,  which 
forces  air  under  pressure  into  a  tank. 

The  air  tank  is  connected  with  the  cylinder, 
and  the  flywheel  being  turned  till  the  engine  is 
in  a  position  to  start,  that  is  when  the  crank  is 
just  above  the  dead  center,  the  compressed-air 
valve  is  then  opened  and  kept  open  until  the 
piston  approaches  the  end  of  its  stroke.  This 
operation  is  repeated  once  or  twice,  if  necessary, 
to  set  the  engine  in  motion. 


24        GAS  AND   OIL   ENGINE   HAND-BOOK 

A  number  of  devices  are  also  in  use,  in  which 
charges  of  gas  and  air  are  forced  into  the  engine 
cylinder,  and  ignited  by  a  separate  and  special 
device,  the  operation  being  repeated  till  the  or- 
dinary ignition  mechanism  comes  into  play. 


FIG.  5 

Compressed  air  starter,  showing  air  storage  tank  and  drive  from 
line  shaft  to  air  compressor. 


Exhaust  gases  stored  by  the  engine  itself,  under 
pressure  in  a  reservoir,  are  also  used. 

Figure  5  shows  a  gas  or  oil  engine  equipped 
with  a  compressed  air  starter.  The  air  compres- 
sor is  belt-driven  from  the  line  shaft.  The  stor- 
age tank,  supply  pipe  to  the  engine  and  starting 
valve  are  plainly  shown. 


GAS  AND   OIL  ENGINE  HAND-BOOK       25 

Compression,  Advantages  of.  High,  but  not 
excessive,  compression  of  the  explosive  charge, 
combined  with  complete  combustion  and  expan- 
sion, are  the  most  important  factors  in  the  eco- 
nomical working  of  gas  and  oil  engines. 

With  a  high  degree  of  compression  the  charge 
of  gas  and  air  becomes  more  homogeneous,  is 
more  rapidly  ignited  and  with  greater  certainty, 
consequently  the  combustion  is  more  complete, 
and  the  force  arising  from  the  explosion  of  the 
charge  greater. 

A  smaller  cylinder  is  required  to  give  out  the 
same  power,  and  a  weaker  charge  can  be  ignited. 
If,  however,  the  compression  be  too  great,  pre- 
mature ignition  will  occur. 

If  the  engine  loses  its  compression,  it  generally 
arises  from  a  defective  condition  of  the  exhaust 
or  inlet- valves,  joints,  or  piston-rings.  The. 
valves  should  be  taken  out  and  carefully  exam- 
ined, and  if  the  valves  do  not  fit  properly  in 
their  seats,  they  should  be  carefully  ground  in 
with  fine  emery  powder  and  oil,  the  emery  being 
afterwards  cleaned  off  with  kerosene. 

If  the  valve  stems  are  too  tight,  they  should  be 
eased  with  a  smooth  file. 

It  is  also  very  important  that  the  degree  of 
compression  be  adjusted  to  suit  the  explosive 
qualities  of  the  fuel  used. 

Compression,  How  to  Calculate.  The  com- 
pression in  atmospheres  of  an  engine  may  be 


26       GAS  AND  OIL  ENGINE   HAND-BOOK 

readily  found  by  dividing  the  cubic  contents  of 
the  piston  displacement  by  the  cubic  contents  of 
the  combustion  chamber  in  cubic  inches,  and 
then  adding  one  to  the  result. 

To  ascertain  the  compression  in  atmospheres 
of  an  engine,  when  the  cubic  contents  of  the 
combustion  chamber  are  known:  Let  S  be  the 
stroke  of  the  piston  in  inches  and  A  the  area  of 
the  cylinder  in  square  inches.  If  C  be  the  con- 
tents of  the  combustion  chamber  in  cubic  inches 
and  N  the  required  compression  in  atmospheres, 
then 

/Cl     ^/      A  \ 

+    1 


Example:  Find  the  compression  in  atmos- 
pheres of  an  engine  of  4-inch  bore  and  6-inch 
stroke,  whose  combustion  chamber  has  a  capacity 
of  18  cubic  inches. 

Answer:  Six  multiplied  by  12.56  equals  75.36, 
which  divided  by  18  gives  4.19,  and  4.19  plus  1 
equals  5.19,  or  the  compression  in  atmospheres 
required. 

If  it  is  desired  to  ascertain  the  compression  in 
atmospheres  of  an  engine,  the  combustion  cham- 
ber of  which  is  of  such  shape  that  its  dimensions 
cannot  be  accurately  calculated,  its  cubic  contents 
may  be  found  by  filling  the  combustion  chamber 
with  water,  and  after  removing  the  water,  ascer- 
taining its  weight  in  ounces,  and  then  multiplying 
the  result  by  1.72.  This  gives  the  capacity  of  the 


GAS  AND  OIL  ENGINE  HAND-BOOK       27 

combustion  chamber  in  cubic  inches.  The  com- 
pression of  the  engine  can  then  be  readily  calcu- 
lated from  the  formula  given  herewith. 

Compression,  How  to  Test  for  Leaks  in. 
To  discover  if  there  are  any  leaks  in  the  com- 
pression of  a  gasoline  motor,  a  small  pressure 
gauge  reading  up  to  at  least  75  pounds  should  be 
screwed  into  the  ignition  tube  opening  or  in  any 
other  suitable  opening  in  the  combustion  chamber. 
When  turning  the  motor  flywheel  slowly  the 
gauge  should  indicate  at  least  70  pounds  per 
square  inch  if  the  compression  is  in  good  condi- 
tion. 

To  test  for  leaks,  fill  a  small  oil  can  with 
soapy  water  and  squirt  round  every  joint  where 
there  may  be  a  possible  chance  for  leakage. 
Get  an  assistant  to  turn  the  flywheel  and  watch 
for  bubbles  at  the  joints. 

If  the  joints  are  all  tight,  next  examine  the 
condition  of  the  inlet  and  exhaust- valves,  and  if 
either  of  them  needs  regrinding  it  should  be  done 
with  fine  emery  powder  a  ad  oil. 

When  the  valves  have  been  ground  to  a  perfect 
fit,  if  the  compression  still  leaks,  the  piston-rings 
should  be  examined,  as  the  trouble  will  be  found 
to  be  there. 

If  there  is  a  leakage  by  the  piston,  a  hissing 
sound  will  be  heard.  This  trouble  may  arise 
from  badly  fitted  or  badly  worn  piston -rings,  the 
cylinder  scored  from  insufficient  or  improper 


28       GAS  AND   OIL, ENGINE  HAND-BOOK 

lubrication,  or  the  cylinder  worn  oval  or  out  of 
round,  or  overheated  from  insufficient  cooling. 

If  the  cylinder  is  worn,  there  is  no  remedy  for 
it  but  reboring. 

Compression,  Loss  of.  If  an  engine  leaks 
compression  it  will  not  pull  its  full  load,  and 
does  not  start  easily.  By  forcing  the  piston  back 
against  its  compression  it  may  be  readily  deter- 
mined whether  it  leaks  or  not.  Examine  both 
the  inlet  and  exhaust-valves  and  see  that  they 
are  fitting  properly.  Force  them  up  and  down  a 
few  times  by  hand  to  make  sure  they  work  freely. 

With  the  engine  at  rest,  take  hold  of  the  fly- 
wheel and  turn  it  backwards  until  the  piston 
moves  in  on  the  compression  stroke  with  consid- 
erable force  and  if  there  is  no  leak  the  engine 
should  move  forward  one-half  or  a  full  revolu- 
tion, depending  on  the  force  with  which  it  was 
driven  in. 

If  the  valves  or  ignition  tube  should  leak  there 
would  be  no  rebound. 

To  find  a  leak  in  the  packing,  remove  the 
piston  from  the  cylinder  and  put  a  light  inside. 

Turn  on  the  water  and  by  looking  in,  the  leak 
may  be  located. 

Before  replacing  a  gasket,  scrape  both  surfaces 
clean.  Use  asbestos  millboard  soaked  in  oil. 

Put  the  gasket  in  place  and  draw  it  up  tight. 

After  the  engine  has  become  warm  draw  up 
the  gasket  several  times  until  the  joint  is  tight. 


GAS  AND  OIL  ENGINE  HAND-BOOK       29 

Connecting-rods.  Connecting-rods  of  gas 
and  oil  engines  are  of  various  shapes  in  cross- 
section,  but  those  principally  in  use  are  made  of 
steel  with  rectangular  or  circular  section,  with  an 
adjustable  bronze  bearing  at  the  crank-pin  end. 

The  crank-pin  end  bolts  should  be  so  propor- 
tioned as  to  have  an  area  of  at  least  25  per  cent 
of  the  mean  cross-section  of  the  rod. 

A  connecting-rod  of  rectangular  section,  when 
made  of  steel,  should  have  a  cross -sectional  area 
at  least  30  per  cent  greater  than  the  circular  one. 
For  a  rod  of  circular  section  the  width  of  the  rod 
should  be  at  least  one-third  its  mean  depth. 

For  small  engines  a  good  and  cheap  form  of 
connecting-rod  may  be  made  of  phosphor  bronze 
or  cast  steel. 

Crank  Shafts.  The  crank  shaft  of  a  gas  or 
oil  engine  should  be  made  of  sufficient  strength 
not  only  to  withstand  the  sudden  pressure  due  to 
the  explosion,  but  also  to  withstand  the  strain 
consequent  upon  the  greater  explosive  pressure 
which  may  possibly  be  caused  by  previous  missed 
explosions.  The  crank  shaft  "should  be  propor- 
tioned with  relation  to  the  area  of  the  cylinder 
and  the  maximum  pressure  of  the  explosion. 

The  mechanical  efficiency  of  an  engine  may  be 
gauged  by  the  strength  of  the  crank  shaft,  because 
if  the  crank  shaft  is  not  sufficiently  strong,  it  will 
spring  at  each  impulse,  causing  the  flywheels  to  run 
out  of  true  and  also  wear  the  bearings  unevenly. 


30        GAS  AND  OIL  ENGINE  HAND-BOOK 

The  balancing  of  the  crank  shaft  and  recipro- 
cating parts  is  an  important  feature  of  a  gas  or 
oil  engine.  With  a  single-cylinder  explosive 
engine,  to  perfectly  accomplish  the  balancing  is 
impracticable.  Most  manufacturers,  therefore, 
only  balance  their  engines  as  far  as  the  recipro- 
cating parts  are  concerned. 

Balancing  by  means  of  a  recess  in  the  rim  of 
the  flywheel  has  the  advantage  of  requiring  no 
extra  metal,  and  is  cheaper  as  regards  workman- 
ship as  compared  with  the  method  of  balancing 
the  crank  shaft  by  means  of  counterweights.  In 
each  of  these  methods,  however,  the  flywheel 
itself  is  out  of  balance,  and  when  rotating  tends 
to  make  the  crank  shaft  run  out  of  true. 

As  it  is  important  that  the  crank  shaft  be  of 
ample  strength,  it  is  the  best  practice  to  make  it 
of  forged  steel  cut  from  the  solid  and  finished 
bright  all  over.  If  the  crank  shaft  be  too  weak, 
it  will  spring  with  the  force  of  the  explosions, 
thereby  causing  undue  wear  on  the  bearings. 

Cycles  of  Gas  and  Oil  Engines.  The  four- 
cycle engine,  having  only  one  working  stroke  or 
impulse  during  each  two  revolutions  of  the  crank 
shaft,  consequently  requires  larger  and  heavier 
flywheels  than  a  two-cycle  engine  in  order  to 
maintain  a  practically  uniform  speed  and  also  to 
transmit  the  power  during  the  idle  strokes  of  the 
engine. 

The    four-cycle    engine    has,    however,    many 


GAS  AND  OIL  ENGINE  HAND-BOOK       31 

advantages  over  the  two-cycle  engine.  The  work- 
ing stroke  or  impulse  is  more  readily  controlled, 
and  during  the  inlet  and  exhaust  strokes  a  longer 
time  is  allowed  for  the  cooling  of  the  valves  and 
the  more  thorough  expulsion  of  the  exhaust 
products  from  the  cylinder  than  is  possible  with 
a  two-cycle  engine. 

In  the  two-cycle  type  of  engine  the  charge  must 
be  independently  compressed  before  entering  the 
cylinder  of  the  engine,  in  some  two-cycle  engines 
this  is  accomplished  in  a  separate  cylinder,  but 
usually  in  the  crank  case  of  the  engine. 

A  greater  quantity  of  lubricating  oil  and 
more  cooling  is  required  with  a  two-cycle  than 
a  four-cycle  engine  on  account  of  the  greater 
amount  of  heat  generated  in  the  same  length  of 
time. 

Six-cycle  or  scavenging  engines  have  been 
largely  used,  in  which  after  the  termination  of 
the  exhaust  stroke,  a  charge  of  air  is  drawn  into 
the  cylinder  and  the  products  of  combustion  thus 
entirely  expelled. 

As  such  engines  have  only  one  working  stroke 
or  impulse  to  every  three,  revolutions  of  the 
crank  shaft,  the  cylinder  and  flywheel  dimensions 
require  to  be  greatly  in  excess  of  those  of  engines 
of  the  four-cycle  type,  necessitating  greater  floor 
space,  increased  weight,  excessive  wear  and  tear 
and  greater  complication  of  the  valve-operating 
mechanism. 


32        GAS   AND   OIL   ENGINE   HAND-BOOK 

Cylinders,  Construction  of.  Cylinders  made 
with  a  loose  head  require  the  joint  to  be  made 
with  great  care.  An  asbestos  or  copper  ring  is 


FIG.  6 

Gas  or  gasoline  engine  cylinder,  with  detachable  water-cooled 
head. 

used  to  make  this  joint,  sometimes  wire  gauze 
with  asbestos  is  used,  which  has  been  found  to 
give  very  good  results. 

Figure  6  shows  a  cylinder  with  a  loose  water- 
jacketed  head  in  which  both  the  inlet  and  exhaust  - 


FlG.  7 

Gas  or  oil  engine  cylinder,  with  cylinder  and  head  cast  integral. 

valves  are  located.  This  style  of  cylinder  has 
feet  or  lugs  on  either  side  to  attach  it  to  the  bed- 
plate. 


GAS  AND   OIL   ENGINE   HAND-BOOK       33 

A  form  of  cylinder  is  shown  in  Figure  7  in 
which  the  cylinder  and  head  are  integral  or  cast 
in  one  piece,  it  has  a  separate  valve-chamber 
(not  shown)  which  bolts  on  the  side  of  the  cylin- 
der and  communicates  with  the  combustion 
chamber  by  a  port  or  passage  shown  in  the  draw- 
ing. This  style  of  cylinder  is  attached  to  the  bed- 
plate by  means  of  a  circular  sleeve  which  fits 
into  an  opening  at  the  end  of  the  bed-plate  and 
is  drawn  up  against  the  circular  flange  shown  by 
means  of  bolts. 

Cylinder,  Method  of  Boring  a.  A  good  way 
to  bore  a  cylinder  is  to  make  a  boring-bar  to  fit 
in  the  drill  socket  of  a  back-geared  drill  press 
and  a  brass  or  phosphor  bronze  bushing  to  fit  in 
the  center  hole  of  the  table  of  the  drill  press. 
The  cylinder  can  be  clamped  to  the  table  of  the 
drill  press  by  its  flange  and  bored  out  with  a 
cutter  set  in  the  boring-bar.  Not  less  than  three, 
and  preferably  four  cuts,  should  be  taken  to 
make  a  good  job.  A  mandril  should  then  be 
made  with  two  flanged  hubs,  one  of  which  should 
be  fastened  to  the  mandril  and  the  other  turned 
slightly  taper  so  as  to  make  a  snug  fit  in  the 
cylinder  bore  when  in  place.  The  ends  of  the 
cylinder  can  then  be  finished  on  the  mandril  and 
a  perfect  job  will  be  the  result.  In  case  a  back- 
geared  drill  press  is  not  handy  the  cylinder  can 
be  clamped  to  the  carriage  of  the  lathe,  bored 
out  with  a  bar  in  the  lathe  centers  and  the  ends 


34       GAS  AND  OIL  ENGINE  HAND-BOOK 

finished  in  the  manner  above  described,  but  it  is 
a  much  slower  job  than  in  a  drill  press.  The 
cutter  for  the  bar  should  be  made  from  a  piece 
of  round  tool  steel  not  less  than  five-eighths  of  an 
inch  diameter.  It  can  then  be  readily  adjusted 
to  any  desired  angle  to  obtain  the  best  cutting 
effect. 

Cylinder  Sweating.  Sometimes  water  will 
collect  in  the  cylinder  as  a  result  of  the  interior 
walls  of  both  the  cylinder  and  cylinder-head 
sweating.  This,  however,  does  not  often  happen 
except  on  very  warm  days  when  a  considerable 
volume  of  cold  water  has  been  allowed  to  flow 
through  the  water-jacket  after  the  engine  has 
been  shutdown,  and  this  seldom  applies  where  the 
thermo-syphon  water-cooling  system  is  used.  It 
is  more  liable  to  happen  where  the  cold  water 
from  a  hydrant  has  been  allowed  to  flow  through 
the  water-jacket. 

Design  of  Gas  and  Oil  Engines.  Gas  and 
oil  engines  should  be  of  substantial  design  in 
order  to  withstand  the  continual  shock  and  vibra- 
tions to  which  they  are  subject,  and  should  be  as 
accessible  as  possible  in  the  working  parts,  which 
may  require  adjustment  while  in  actual  service. 
The  starting  gear  and  other  parts  to  be  handled 
by  the  attendant  when  starting  and  running  the 
engines  should  be  placed  in  close  proximity  to 
each  other. 

Simplicity  in  construction  is  the  essential  fea- 


GAS  AND  OIL  ENGINE  HAND-BOOK       35 

iure  of  a  gas  or  oil  engine.  The  oil  engine  is  a 
machine  intended  for  use  in  any  part  of  the 
world  where  its  fuel  is  obtainable,  and  where, 
perhaps,  no  mechanic  is  available.  Accordingly, 
all  the  mechanism  should  be  arranged  so  as  to 
be  easily  removed  for  examination  and  repair. 
The  igniting  device,  as  well  as  the  carbureter  or 
vaporizer,  should  be  so  designed  as  to  facilitate 
removal  and  repair.  A  gas  or  oil  engine,  to  be 
successful  mechanically  and  commercially,  should 
be  so  designed  that  it  can  be  successfully  oper- 
ated, cleaned  and  adjusted  by  unskilled  attend- 
ants. 

Deep  Well  Pumping  Plants.  A  deep  well 
pumping  plant  operated  by  a  gasoline  engine 
through  a  single  reduction  gearing  is  illustrated 
in  Figure  8,  the  pump  is  of  the  single-acting  type 
and  is  connected  to  the  reduction  gear  by  means 
of  a  pitman-rod  with  a  forked  lower  end.  Such 
plants  are  also  used  for  draining  mines  and 
quarries. 

Dry  Batteries.  In  one  respect  dry  batteries 
have  a  decided  advantage  over  liquid  batteries 
for  ignition  purposes,  from  the  fact  that  on 
account  of  their  high  internal  resistance  they  can- 
not be  so  quickly  deteriorated  by  short  circuiting. 

On  account  of  this  high  internal  resistance,  dry 
batteries  will  not  give  so  large  a  volume  of  cur- 
rent as  liquid  batteries,  but  a  set  of  dry  batteries 
may  be  short  circuited  for  five  minutes  without 


36       GAS  AND  OIL  ENGINE  HAND-BOOK 

apparent   injury   and    will   recuperate    in    from 
twenty  to  thirty  minutes,  while  a  liquid  battery 


FIG.  8 

Deep  well  pumping  plant,  showing  engine,  reduction  gear, 
pitman-rod  and  pump. 

would   in  all  probability  be    badly  deteriorated 
under  the  same  conditions. 

A  dry  battery  of  the  usual  type  consists  of  a 


GAS  AND  OIL  ENGINE   HAND-BOOK       37 

zinc  cell  which  forms  the  negative  element  of  the 
battery.  The  electrolyte  is  generally  a  jelly-like 
compound  containing  sal-ammoniac,  chloride  of 
zinc,  etc.  The  carbon  or  positive  element  is 
enclosed  in  a  sack  or  bag  containing  dioxide  of 
manganese  and  crushed  coke,  which  are  the 
depolarizing  agents  of  the  battery. 

Dynamometer.  A  dynamometer  is  a  form  of 
equalizing  gear  which  is  attached  between  a 
source  of  power  and  a  piece  of  machinery  when 
it  is  desired  to  ascertain  the  power  necessary  to 
operate  the  aforesaid  machinery  with  a  given  rate 
of  speed. 

Efficiency,  Mechanical.  The  mechanical 
efficiency  of  a  gas  or  oil  engine  depends  on  its 
design,  workmanship  and  proper  lubrication,  and 
also  on: 

The  proper  mixture  of  air  and  fuel. 

The  correct  degree  of  compression. 

The  correct  point  of  ignition. 

The  duration  and  completeness  of  combus- 
tion. 

The  rapidity  and  amount  of  expansion. 

Efficient  governing  and  free  exhaust. 

If  any  doubts  exist  as  to  the  engine  giving  out 
its  proper  power,  a  brake  test  should  be  made. 

To  ascertain  the  mechanical  efficiency  of  a  gas 
or  oil  engine,  both  indicator  and  brake  horse- 
power tests  should  be  made,  then  if  I.H.P.  be 
the  indicated  horsepower  and  B.H.P.  the  actual 


38       GAS  AND  OIL  ENGINE   HAND-BOOK 

or  brake  horsepower  of  the  engine  and  M.E.  be 
its  mechanical  efficiency,  then 

B.H.P. 

M'E-  --  TKP. 

If  the  brake  horsepower  of  an  engine  be  7.5 
and  the  indicated  horsepower  be  10,  then  the 
mechanical  efficiency  will  be 

M.E.  =  H 

which  equals  75  per  cent. 

In  text-books  the  efficiency  of  an  engine  is 
usually  considered  as  the  relation  between  the 
heat-units  consumed  by  the  engine  and  the  work 
or  energy  in  foot-pounds  given  out  by  it.  If  the 
heat-units  (which  are  measured  by  the  quantity 
of  fuel  supplied  to  the  engine)  be  large  compared 
to  the  work  or  energy,  given  out  by  the  engine, 
its  efficiency  is  small. 

Efficiency,  Thermal.  The  ratio  of  the  heat 
utilized  by  the  engine,  as  shown  by  the  power 
developed,  as  compared  with  the  total  heat  con- 
tained in  the  fuel  absorbed  by  the  engine,  is 
known  as  the  thermal  efficiency.  This  can  be 
obtained  by  the  following  formula : 

Let  F  ^consumption  of  fuel  in  pounds  per 
brake  horsepower  per  hour,  and 

C= calorific  value  of  the  fuel  per  pound  in 
heat  units,  then 

_  42.63  X  60 

CXF 


GAS  AND  OIL  ENGINE  HAND-BOOK       39 

The  thermal  efficiency  of  the  oil  engine  is  low 
as  compared  with  the  gas  engine.  The  best  gas 
engine  makers  now  claim  a  thermal  efficiency  for 
their  engines  of  27  per  cent,  whereas  it  is  believed 
the  maximum  thermal  efficiency  recorded  by  any 
oil  engine  now  in  regular  use  is  but  18  per  cent. 

Electricity,  Forms  of.  Electricity  or  elec- 
trical energy  may  be  generated  in  several  ways — 
mechanically,  chemically  and  statically  or  by 
friction.  By  whatever  means  it  is  produced, 
there  are  many  properties  which  are  common  to 
all.  There  are  also  distinctive  properties.  The 
current  supplied  by  a  storage  battery  will  flow 
continuously  until  the  battery  is  practically  ex- 
hausted, while  the  current  from  a  dry  battery  can 
only  be  used  intermittently:  that  is,  it  must  have 
slight  periods  of  rest,  no  matter  how  short  they 
may  be. 

The  dynamo  or  magneto  current  is  primarily 
of  an  alternating  nature  or  one  which  reverses  its 
direction  of  flow  rapidly.  In  use,  this  alternating 
current  is  changed  into  a  direct  or  continuous 
current  flowing  in  one  direction  only,  by  means 
of  a  commutator.  Any  of  the  forms  described 
are  capable  of  igniting  an  explosive  charge  in  a 
motor  cylinder,  but  the  static  or  frictional  form 
of  electricity  is  not  used  for  this  purpose  on 
account  of  its  erratic  nature. 

Electric  Light  Outfits.  Although  gas  and  oil 
engines  for  electric  lighting  purposes  are  of 


40       GAS  AND   OIL   ENGINE   HAND-BOOK 

special  design,  the  lights  may  sometimes  flicker. 
Flickering  in  the  incandescent  lights  may  be 
located  by  close  inspection  of  the  engine  and 
dynamo,  and  may  be  due  either  to  the  flywheels, 
the  governor  or  the  belt.  To  locate  this  defect 
and  remedy  it,  notice  the  lamps  carefully.  If  the 
variations  in  the  light  are  due  to  lack  of  weight 
in  the  rim  of  the  flywheel,  these  variations  will 
be  seen  to  coincide  with  the  revolutions  of  the 
engine.  Again,  if  the  variation  in  the  lights  is 
only  periodical,  then  this  defect  should  be 
remedied  by  adjustment  of  the  governor.  Exam- 
ine the  governing  mechanism  of  the  engine. 
If  the  variation  is  caused  by  the  governor  acting 
too  slowly,  then  adjust  the  governor  so  as  to 
cause  more  rapid  action  upon  the  controlling 
mechanism. 

The  cause  of  the  trouble  may  not  be,  as 
already  suggested,  in  the  flywheel  or  in  the 
adjustment  of  the  governor,  but  in  the  belt, 
which  is  frequently  the  sole  cause  of  flickering  in 
the  lights.  The  engine  and  dynamo  pulleys  over 
which  the  belt  runs  should  be  exactly  in  line  with 
each  other.  The  belt  should  be  made  endless, 
or  if  jointed  the  joints  should  be  very  carefully 
made.  A  thick,  uneven  joint  in  the  belt  will 
cause  a  flicker  in  the  lights  each  time  it  passes 
over  the  dynamo  pulley. 

Figure  9  shows  a  two-cycle  gasoline  engine 
directly  connected  to  a  dynamo,  both  engine 


GAS   AND  OIL  ENGINE   HAND-BOOK       41 

and   dynamo   being    mounted    on    a    cast   iron 
base. 

To  secure  a  steady  light  with  gas  or  oil 
engines,  the  practice  has  been  to  place  a  flywheel 
upon  the  dynamo  shaft,  as  the  speed  of  some 
engines  sometimes  varies  as  much  as  5  per  cent. 
The  constructional  details  of  some  gas  engines 


FIG.  9 

Electric  light  outfit,  showing  two-cycle  engine  direct-connected 
to  dynamo.^ 


used  for  this  purpose  have  been  so  considerably 
improved  that  the  dynamo  flywheel  is  not  consid- 
ered necessary. 

This  uniform  speed  has  been  largely  secured 
by  increasing  the  diameter  and  weight  of  the 
flywheels,  together  with  an  improved  method  of 
direct  balancing,  the  balance  being  fitted  to  the 


42       GAS  AND  OIL   ENGINE  HAND-BOOK 

crank,  instead  of  to  the  rim  of  the  flywheel, 
which  is  usually  the  case  with  ordinary  engines. 
Very  sensitive  governing  gear,  however,  is  neces- 
sary. 

Exhaust,  Cause  of  Smoky.  Smoke  coming 
from  the  exhaust  of  a  gas  or  oil  engine  is  due  to 
one  of  two  conditions:  Over-lubrication — too 
much  lubricating  oil  being  fed  to  the  cylinder  of 
the  engine,  or  too  rich  a  mixture,  that  is,  too 
much  fuel  and  an  insufficient  supply  of  air. 

The  first  condition  may  be  readily  detected  by 
the  smell  of  burned  oil  and  a  yellowish  smoke. 
The  second,  by  a  dense  white  smoke  accom- 
panied by  a  pungent  odor. 

Explosions  in  the  Inlet-pipe.  These  usually 
only  occur  in  engines  with  mechanically  operated 
inlet-valves,  a  weak  or  a  too  rich  charge  of 
explosive  mixture  being  ignited  burns  slowly  in 
the  combustion  chamber  and  when  the  piston  has 
reached  the  end  of  the  exhaust  stroke  and  the 
inlet-valve  commences  to  rise,  the  burning  gases 
in  the  combustion  chamber  ignite  the  explosive 
mixture  in  the  inlet-pipe. 

A  further  loss  arises  from  this  kind  of  explo- 
sion, as  on  the  next  admission  or  suction  stroke 
these  partly  burned  gases  enter  the  combustion 
chamber,  instead  of  an  entirely  fresh  supply  of 
gas  and  air,  and  consequently  retard  the  com- 
bustion and  reduce  the  power  of  the  next  explo- 
sion. 


GAS  AND   OIL  ENGINE  HAND-BOOK       43 

Explosions,  Weak.  These  may  be  caused 
from  improper  mixture,  ignition  set  too  late,  loss 
of  compression  from  defective  piston,  valves,  or 
joints. 

Fire  Insurance.  The  following  are  the  gen- 
eral requirements  of  the  various  boards  of  fire 
underwriters  for  the  installation  and  use  of  oil 
engines : 

LOCATION  OF  ENGINE.  Engine  shall  not  be 
located  where  the  normal  temperature  is  above 
95  degrees  Fahrenheit,  or  within  ten  feet  of  any 
fire. 

If  enclosed  in  room,  same  must  be  well  venti- 
lated, and  if  room  has  a  wood  floor,  the  entire 
floor  must  be  covered  with  metal  and  kept  free 
from  the  drippings  of  oil. 

If  engine  is  not  enclosed,  and  if  set  on  a  wood 
floor,  then  the  floor  under  and  three  feet  outside 
of  it  must  be  covered  with  metal. 

OIL  FEED  TANK.  If  located  inside  of  build- 
ing, shall  not  exceed  five  gallons  capacity,  and 
must  be  made  of  galvanized  iron  or  copper,  not 
less  than  No.  22  B.  &  S.  Gauge,  and  must  be 
double  seamed  and  soldered,  and  must  be  set  in 
a  drip  pan  on  the  floor  at  the  base  of  the 
engine. 

Fire  Pot  or  Muffler.  Gas  or  oil  engines  hav- 
ing a  relief-exhaust  in  the  form  of  a  port  or 
opening,  which  is  uncovered  by  the  piston  shortly 
before  the  end  of  the  explosion  or  working  stroke 


44       GAS  AND  OIL  ENGINE  HAND-BOOK 


of  the  engine,  should  have  the  fire  pot  or  muffler 
connected  with  the  relief-exhaust  port  opening 
and  a  separate  pipe  provided  for  the  regular 
exhaust  valve  opening.  If  this  is  not  done,  back 
pressure  from  the  relief-exhaust  will  oppose  the 
free  discharge  of  the  exhaust  gases  from  the  main 
exhaust  valve,  thereby  causing  an  excessive 


FIG.  1O 

Muffler  installation,  showing  muffler  connected  to  relief-exhaust 
on  left-hand  side  of  engine. 

amount  of  the  products  of  combustion  to  be  left 
in  the  cylinder  at  the  termination  of  the  exhaust 
stroke.  Figures  10  and  11  show  methods  of 
attaching  the  fire  pot  or  muffler  to  the  relief- 
exhaust  on  the  left  and  right-hand  sides  of  the 
engine  respectively.  The  main  exhaust  connec- 
tion is  omitted  in  Figure  11. 


GAS  AND  OIL  ENGINE  HAND-BOOK        45 


Flash  Test  of  Oils.  The  apparatus  used  for 
this  purpose  consists  of  a  small  copper  vessel  in 
which  the  oil  to  be  tested  is  placed.  This  vessel 
is  immersed  in  a  larger  vessel  containing  water, 
which  forms  part  of  the  upper  portion  of  the 
apparatus. 

A  thermometer  is  suspended    with    its    lower 


FIG.  11 

Muffler  installation,  showing  muffler  connected  to  relief-exhaust 
on  right-hand  side  of  engine. 


part  in  the  oil.  A  heating  lamp  placed  under 
the  receptacle  containing  the  water  raises  the 
temperature  of  both  water  and  oil  as  required. 
A  lighted  taper  is  passed  to  and  fro  over  the  top 
of  the  oil  as  it  becomes  heated.  When  the  vapor 
given  off  by  the  oil  flashes  the  temperature  is 
noted,  and  that  is  termed  the  flashing  point  of 
the  oil  tested. 


46       GAS  AND  OIL  ENGINE   HAND-BOOK 

Flywheels.  The  flywheels  of  a  gas  or  oil 
engine  require  careful  keying  on  the  crank  shaft. 
If  the  keys  are  not  a  good  fit  and  are  not  driven 
home  properly  the  engine  may  knock  when  run- 
ning. Two  keys  are  usually  fitted  to  the  shaft  of 
large  engines,  one  being  a  feather  key,  which  is 
fitted  in  a  keyway  in  the  shaft  as  well  as  in  a 
key  way  cut  in  the  flywheel  hub,  the  second  key 
being  a  taper  key  with  a  gib-head,  which  is 
recessed  in  the  flywheel  hub  and  made  concave 
on  the  lower  side  to  fit  the  shaft. 

WEIGHT  OF  RIMS  OF  FLYWHEELS.  The  weight 
of  the  rim  of  the  flywheel  is  the  only  portion 
which  enters  into  the  following  calculations,  the 
weight  of  the  web  or  spokes  and  hub  being 
neglected. 

Let  M.P  be  the  mean  pressure  of  the  com- 
pression, and  A  the  area  of  the  cylinder  in  square 
inches.  If  S  be  the  stroke  of  the  piston  in 
inches,  and  N  the  number  of  revolutions  per 
minute  of  the  engine,  let  D  be  the  outside  diam- 
eter of  the  flywheel  in  inches  and  W  its  required 
weight  in  pounds,  then 

_  M.P  X  A  X  S  X  N 
2560  X  D 

DIAMETER  OF  RIMS  OF  FLYWHEELS.  An 
engine  that  is  intended  to  operate  at  a  slow  rate 
of  speed  and  consequently  with  a  high  degree  of 
compression,  will  require  a  flywheel  of  much 


GAS  AND   OIL   ENGINE   HAND-BOOK       47 

greater  diameter  and  weight  than  a  higher  speed 
engine  of  the  same  bore  and  stroke.  It  may  be 
well  to  remember  that  within  certain  limitations 
the  diameter  and  weight  of  a  flywheel  should  be 
as  small  as  is  possible,  as  an  increase  in  either 
means  a  reduction  in  engine  speed,  increased 
friction  and  a  consequent  loss  of  power. 

To  ascertain  the  proper  diameter  of  a  flywheel 
when  all  other  conditions  are  known,  if  D  be  the 
required  diameter  of  the  flywheel  in  inches,  then 

_  M.P  X  A  X  S  X  N 
2560  X  W 

Two  flywheels  should  be  used  for  steady  run- 
ning, at  the  same  time,  they  equalize  the  wear  on 
the  crank-shaft  bearings.  They  should  be  care- 
fully turned  and  balanced,  and  run  perfectly  true 
at  full  speed.  If  one  wheel  is  used,  it  should  be 
of  heavy  construction  and  supported  by  an  out- 
side bearing. 

Foundation  Bolts.  The  number  and  size  of 
these  are  usually  determined  by  the  builder  of  the 
engine  and  indicated  by  the  number  of  holes  in 
the  engine  base.  The  bolts  should  be  long 
enough  to  extend  from  the  bottom  of  the  founda- 
tion to  from  two  and  a  half  to  four  inches  above 
the  capstone. 

They  should  have  iron  anchor  plates  at  the  bot- 
tom and  be  threaded  at  the  top  to  receive  a 
nut. 


48       GAS  AND   OIL  ENGINE   HAND-BOOK 

Three  or  four  days  after  the  foundation  Is 
completed,  and  the  cement  firmly  set,  the  engine 
may  be  placed  in  position  and  bolted  down  ready 
for  work. 

Foundations.  A  concrete  foundation,  if  prop- 
erly constructed,  is  the  best.  While  founda- 
tions are  usually  built  of  brick  or  stone  laid  in 
cement,  a  foundation  may  be  of  concrete,  mixed 
as  follows:  One  part  of  cement,  two  parts  of 
coarse  sand,  five  parts  of  fine  crushed  stone  or 
coarse  gravel. 

It  is  desirable  to  have  the  capstone  from  3  to 
6  inches  wider  and  longer  than  the  base  of  the 
engine.  The  depth  of  the  foundation  will  depend 
entirely  upon  the  condition  of  the  ground  in  the 
vicinity  where  the  engine  is  to  be  set  up. 

The  foundation  should  always  go  below  the 
freezing  line  and  as  much  below  as  is  necessary 
to  get  a  firm  base.  Ordinarily  from  3  to  4  feet 
is  sufficient  for  small  engines  of  from  4  to 
12  horsepower.  For  larger  engines  from  15 
to  40  horsepower,  4  to  6  feet  is  not  too  much. 

Where  possible,  the  sides  of  the  foundation 
should  have  a  slope  or  batter  not  less  than 
15  degrees. 

Four-cycle  Engine,  Construction  of.  The 
general  construction  of  a  four-cycle  gas  or  oil 
engine  is  plainly  shown  in  Figure  12.  The 
engine  is  equipped  with  both  hot  tube  and  elec- 
tric ignition  and  an  atmospherically  or  suction 


GAS  AND   OIL   ENGINE   HAND-BOOK       49 


operated  inlet- valve.  Reference  to  the  table  and 
the  corresponding  letters  in  the  drawing  will  give 
a  clear  understanding  of  the  use  of  the  various 
parts  of  the  engine. 


FIG.  12 

Vertical  longitudinal  section  of  four-cycle  motor,  showing  con- 
structional details. 


A — Crank  Case.  M — 

B— Cylinder. 

C— Crank  Shaft.  N— 

D — Connecting-rod. 
E— Piston.  O- 

F— Piston  Wrist  Pin.  P- 

G— Upper  Hand  Hole  Plate.  R- 
H— Lower  Hand  Hole  Plate.  T- 
J— Oil  Test  Plug.  U 

K— Drain  Plug.  V- 

L — Splash  lubricator. 


Crank  Pin  bearing  Ad- 
justing Nut. 

Crank  Pin  bearing  Lock 
Nut. 

Cylinder  Oiler. 

Ignition  Tube. 

•Admission  Valve. 

Piston-rings. 

•Inlet  for  cooling  water. 

Outlet  for  cooling  water. 


Four-cycle  Engine,  Operation  of.  A  four- 
cycle engine  has  only  one  working  stroke  or 
impulse  for  each  two  revolutions.  During  these 


50       GAS  AND  OIL  ENGINE   HAND-BOOK 

two  revolutions  which  complete  the   cycle  of  the 
engine,  six  operations  are  performed: 

1.  Admission  of  an  explosive  charge  of  gas  or 
gasoline  vapor  and   air  to  the   cylinder   of  the 
engine. 

2.  Compression  of  the  explosive  charge. 

3.  Ignition  of  the  compressed  charge  by  a  hot 
tube  or  an  electric  spark. 

4.  Explosion  or  extremely  sudden  rise  in  the 
pressure    of   the    compressed    charge,    from    the 
increase  in  temperature  after  ignition. 

5.  Expansion  of  the  burning  charge  during  the 
working  stroke  of  the  engine  piston. 

6.  Exhaust  or  expulsion  of  the  burned  gases 
from  the  engine  cylinder. 

As  pressure  increases  with  a  rise  in  tempera- 
ture, which  in  an  engine  the  moment  after 
ignition  has  taken  place  is  about  2,700  degrees 
Fahrenheit,  the  higher  the  temperature  of  the 
ignited  gases,  the  greater  would  be  the  pressure. 
As  this  pressure  is  expended  in  work  on  the 
engine  piston,  the  whole  of  it  might,  if  expansion 
of  the  burning  gases  were  continued  long  enough, 
be  utilized.  Full  utilization  of  the  expansion  of 
the  gases  is  impossible  from  a  mechanical  point 
of  view.  The  expansion  of  the  gases  should  be 
as  rapid  as  possible,  as  the  faster  the  piston 
uncovers  the  cylinder  wall,  the  less  time  will  be 
left  for  the  transmission  of  heat  or  energy  to  the 
cylinder  wall.  Gasoline  vapor  or  gas  in  them- 


GAS  AND  OIL  ENGINE  HAND-BOOK       51 

selves  are  not  combustible,  but  must  be  mixed 
with  a  certain  amount  of  air  before  ignition  and 
consequent  combustion  can  be  effected.  The 
combustion  of  the  gases  is  not  instantaneous,  but 
continues  during  the  entire  working  stroke  of  the 
engine  piston. 

Four-cycle  Engine,  Principle  of.  Figure  13 
gives  four  diagrammatic  views  of  the  operation  of 
a  four-cycle  gas  or  oil  engine.  It  shows  an  inlet- 
valve  A,  valve-openings  B,  cylinder  C,  cam  D, 
exhaust  valve  E,  combustion  chamber  F,  piston 
G,  valve  springs  H,  crank  case  J,  connecting-rod 
K  and  crank-pin  L. 

Diagram  No.  1  shows  the  piston  about  to  draw 
in  a  charge  of  explosive  mixture,  the  suction  or 
drawing  in  of  the  charge  continues  until  the 
piston  has  reached  the  position  shown  in  Diagram 
No.  2.  Then  the  piston  returns  until  it  arrives 
at  the  position  shown  in  Diagram  No.  3,  com- 
pressing the  charge  of  mixture  during  this  opera- 
tion. Just  before  the  piston  has  reached  the  end 
of  its  travel  in  this  direction,  the  charge  under 
compression  is  ignited  either  by  an  incandescent 
tube  or  by  an  electric  spark  and  the  force  of  the 
explosion  drives  the  piston  back  to  the  position 
shown  in  Diagram  No.  4,  when  the  exhaust-valve 
is  opened  by  means  of  the  cam  and  valve-lifter 
rod.  The  exhaust  valve  remains  open  until  the 
piston  has  reached  the  position  shown  in  Dia- 
gram No.  1.  Then  it  closes,  the  piston  again 


52       GAS  AND   OIL  ENGINE   HAND-BOOK 


FiG    13 

Four-cycle  motor  diagram,  showing  the  various  operations  dur- 
iug  the  cycles. 


GAS  AND   OIL  ENGINE   HAND-BOOK        53 

commences  to  draw  in  a  charge  of  explosive  mix- 
ture and  the  cycle  of  operation  of  the  engine  is 
repeated.  As  it  requires  four  strokes  of  the 
piston  or  two  complete  revolutions  of  the  crank 
shaft  to  complete  the  cycle,  there  is  consequently 
only  one  impulse  every  two  revolutions  or  one 
working  piston  stroke  out  of  four. 

Four-cycle  Marine  Engines.  A  single-cylinder 
four-cycle  engine  is  shown  in  Figure  14.  This 
style  of  engine  may  be  used  for  either  marine  or 
automobile  work,  being  light  in  weight,  simple  in 
construction  and  made  in  sizes  from  4j  to  10 
horsepower. 

A  two-cylinder  engine  of  similar  construction 
to  the  one  just  described  is  illustrated  on  the 
front  page  of  this  work.  These  engines  are  from 
9  to  20  horsepower.  Such  engines  are  being 
greatly  used  for  motor  launches  on  account  of 
their  light  weight  and  great  power. 

Friction  Clutches.  When  fast-and-loose  pul- 
leys or  friction  clutches  are  used  the  advantages 
gained  are:  the  ease  with  which  the  engine  can 
be  started,  the  loose  pulley  or  friction  clutch 
only,  instead  of  the  whole  line  shaft,  has  to  be 
turned  when  the  plant  is  started,  and  in  case  of 
accident  or  other  emergency  necessitating  the 
quick  stopping  of  the  revolving  machinery,  this 
can  be  accomplished  at  once  by  simply  moving 
over  the  lever  of  the  friction  clutch  or  tight-and- 
loose  pulleys.  Otherwise  the  heavy  flywheels  of 


54       GAS  AND  OIL  ENGINE   HAND-BOOK 


the  engine  would  keep  .revolving  for  some  time 
after  the  fuel  supply  of  the  engine  is  shut  off,  and 


FIG.  14 

Side  and  end  views  of  a  single  vertical  cylinder  marine  or  auto- 
boat  engine. 


GAS  AND  OIL  ENGINE  HAND-BOOK       55 

being  directly  connected  by  belt  to  the  shafting 
and  machinery,  the  whole  plant  is  in  motion  as 
long  as  the  flywheels  keep  revolving. 

Fuel  Consumption  of  Gas  and  Oil  Engines. 
The  fuel  consumption  of  an  engine  is  always  one 
of  grave  importance  to  the  purchaser,  as  well  as 
to  the  manufacturer. 

Ordinarily  about  IT$  pints  of  gasoline  or 
about  15  feet  of  natural  gas,  per  horsepower  per 
hour  under  full  load,  will  cover  the  fuel  con- 
sumption. That  is,  when  the  fuels  used  are  of 
standard  quality  and  the  water  comes  from  the 
water  jacket  at  a  temperature  of  about  140 
to  160  degrees  Fahrenheit. 

The  temperature  of  the  water  in  the  jacket 
around  the  cylinder  has  a  great  deal  to  do  with 
fuel  consumption. 

To  economize  on  the  fuel  consumption  of  an 
engine  the  following  points  should  be  observed: 

1.  To  keep  the  jacket  water  at   160  degrees 
Fahrenheit. 

2.  To  run  the  engine  at  a  medium  speed. 

3.  To  use  a  good  standard  grade  fuel. 

4.  To  see  that  every  charge  the  engine  takes  is 
exploded,  for  which  a  proper  mixture  and  a  good 
spark  or  hot  tube  are  necessary. 

5.  The  admission  valve  should  close  properly 
between  charges,  so  as  not  to  allow  a  continuous 
flow  of  fuel  into  the  engine. 

6.  Never  throttle  the  fuel  so  closely  that  the 


56       GAS  AND  OIL   ENGINE   HAND-BOOK 

engine   cannot  get   a  full    charge  every  time    it 
needs  it. 

7.  Be  sure  that  there  is  no  leak  in  the  supply 
or  overflow  pipes  where  fuel  can  escape. 

8.  When  gasoline  or  kerosene  is  used,  be  sure 
that  there  is  no  leak  in  the  supply  tank. 

9.  See  that  the  exhaust  and  inlet  valves  seat 
properly    and    do  not    leak.     The    piston -rings 
should  hold  the  pressure  due  to  the  explosion. 

Fuel  Gas  Oil.  An  oil  known  as  fuel  gas  oil  is 
procured  in  the  process  of  fractional  distillation 
after  the  lighter  oils  and  the  illuminating  oils 
have  been  taken  off.  Tests  of  samples  of  this 
fuel  gas  oil,  the  characteristics  of  which  vary  con- 
siderably, are  given  in  the  following  table: 

FUEL    GAS    OIL. 

Specific  gravity 0.832            .878 

Beauine" 36°              30.2° 

Flash-point 144°  F.  298°  F. 

Fire  test 183°  F.  247°  F. 

This  fuel  is  much  used  in  oil  engines  in  the 
United  States.  With  the  heavier  grades  a  slight 
deposit  of  carbon  is  left  in  the  engines,  which 
requires  periodical  removing. 

Gas  Bag.  The  gas  bag  of  a  gas  engine 
should  be  entirely  of  vulcanized  rubber,  or  it 
may  be  made  with  an  iron  frame  and  rubber 
sides. 

The  gas  bag  serves  its  purpose  better  the 
nearer  it  is  to  the  engine.  As  the  pulsating  of 


GAS  AND  OIL  ENGINE  HAND-BOOK       57 

the  bag  endangers  its  pulling  off  the  pipe,  care 
should  be  taken  to  secure  the  openings  of  the 
bag  to  the  pipe  by  winding  soft  iron  or  copper 
wire  around  them. 

As  oil  destroys  rubber  and  changes  it  into  a 
sticky,  viscous  mass,  the  gas  bag  should  be 
placed  out  of  reach  of  any  oil  which  might  be 
liable  to  splash  upon  it. 

Gases,  Expansion  of.  All  gases  expand 
equally,  ?fa  part  of  their  volume  for  each  degree 
of  temperature,  Centigrade,  or  TtT  part  of  their 
volume  for  each  degree  of  temperature,  Fahren- 
heit. 

Gasoline,  How  Obtained.  Gasoline,  ben- 
zine, naphtha  and  the  kindred  hydrocarbons  are 
the  products  of  crude  mineral  oil. 

They  are  separated  from  the  crude  oil  by  a 
process  of  distillation.  The  process  is  very  sim- 
ilar to  that  of  generating  steam  from  water. 

By  the  application  of  heat,  water  raised  to  a 
temperature  of  212  degrees  Fahrenheit  changes 
from  a  liquid  to  a  gaseous .  state,  called  steam. 
This  conversion  is  only  temporary.  If  steam  is 
confined  and  cooled  to  a  certain  point  it  will 
quickly  return  to  its  liquid  state,  water,  by  the 
process  known  as  condensation. 

Crude  mineral  oil  subjected  to  heat  will  give 
off,  in  the  form  of  vapor,  such  products  as  gaso- 
line, benzine,  naphtha,  etc.  The  degrees  of 
heat  at  which  these  products  are  separated  are 


58       GAS  AND  OIL  ENGINE  HAND-BOOK 

comparatively  low.  Various  degrees  of  heat  will 
separate  the  distinct  products.  As  a  means  of 
illustration,  say  that  crude  oil  raised  to  a  temper- 
ature of  110  degrees  gives  off  vapor  which  when 
cooled  will  liquefy  into  what  is  known  as  naphtha, 
benzine  at  125  degrees,  and  gasoline  at  140 
degrees.  These  degrees  of  temperature  are  not 
authentic — simply  used  to  illustrate. 

After  these  lighter  products  are  separated  there 
yet  remains  the  thick,  oily  liquid  from  which  the 
various  lubricating  oils  are  prepared. 

Kerosene  oil  is  one  of  the  principal  products  of 
crude  oil,  and  the  oily  sediment  which  frequently 
accumulates  in  the  bottom  of  the  tank  or  can  in 
which  gasoline  is  confined  is  kerosene  oil,  which 
distills  over  in  small  quantity  with  the  vapor  of 
gasoline. 

Gasoline  or  Kerosene  Fires.  In  case  of  fire 
due  to  gasoline  or  kerosene,  use  fine  earth,  flour 
or  sand  on  top  of  the  burning  liquid.  Never 
use  water,  it  will  only  serve  to  float  the  gasoline 
or  kerosene  and  consequently  spread  the  flames. 

A  dry  powder  can  be  used  for  this  purpose 
which  will  extinguish  the  fire  in  a  few  seconds. 
It  is  made  as  follows:  Common  salt,  15  parts — 
sal-ammoniac,  15  parts — bicarbonate  of  soda, 
20  parts.  The  ingredients  should  be  thoroughly 
mixed  together  and  passed  through  a  fine  mesh 
sieve  to  secure  a  homogeneous  mixture. 

If  by  any  chance  a  tank  of  gasoline  or  kero- 


GAS  AND   OIL  ENGINE   HAND-BOOK       59 

sene  takes  fire  at  a  small  outlet  or  leak,  run  to 
the  tank  and  not  away  from  it,  and  either  blow 
or  pat  the  flame  out.  Never  put  water  on  burn- 
ing gasoline  or  kerosene,  the  gasoline  or  kerosene 
will  float  on  top  of  the  water  and  the  flames 
spread  much  more  rapidly.  Throw  fine  earth, 
sand  or  flour  on  top  of  the  burning  liquid.  Flour 
is  best.  The  best  extinguisher  for  a  fire  of  this 
kind  in  a  room  that  may  be  closed,  is  ammonia. 
Several  gallons  of  ammonia,  thrown  in  the  room 
with  such  force  as  to  break  the  bottles  which 
contain  it,  will  soon  smother  the  strongest  fire  if 
the  room  be  kept  closed. 

Gasoline  explosions  are  often  due  to  a  pressure 
within  a  tightly-closed  container,  caused  by  high 
temperature,  which  vaporizes  or  gasifies  the  liquid 
within. 

The  changing  of  the  liquid  to  the  gaseous  state 
causes  expansion,  and  if  there  is  no  vent  or  safety 
valve  connection  the  pressure  within  rises  to  a 
point  sufficient  to  cause  an  explosion. 

Gasoline  Pump,  A  combined  gasoline  pump 
and  gravity  gasoline  feed  is  shown  in  Figure  15. 
The  gasoline  is  pumped  into  the  cup  to  the  right 
of  the  pump  and  is  from  this  point  drawn  into  the 
inlet-pipe  of  the  engine  by  the  inductive  or  suc- 
tion action  of  the  piston  of  the  engine.  The 
supply  of  gasoline  to  the  engine  is  regulated  by 
means  of  a  needle- valve,  the  surplus  gasoline  fed 
to  the  cup  is  carried  back  to  the  supply  tank 


60        GAS  AND   OIL   ENGINE   HAND-BOOK 


through  the  pipe  in  the  center  of  the  cup.     By 
this  method  a  constant  level  is  maintained  in  the 

cup,  thus  ensur- 
ing a  uniform 
supply  of  gaso- 
line to  the  engine 
at  all  times. 

Gasoline  Trac- 
ts i  o  n  Engines. 
From  the  result 
of  experience  it 
has  been  found 
that  gasoline 
traction  engines 
require  a  double 
cylinder  con- 
struction, as  the 
duty  of  the  en- 
gine is  to  not 
only  drive  the 
traction  gearing 
but  to  propel 
itself  over  the  roads.  It  is  found  that  for  success- 
ful work  in  the  field,  which  has  heretofore  been 
occupied  by  the  steam  traction  engine,  a  gas- 
oline engine  of  from  30  to  40  brake  horsepower 
must  be  used.  In  an  engine  producing  this 
amount  of  power  in  a  single  cylinder,  the  sudden 
impulses  at  intermittent  intervals  would  require 
for  successful  operation  a  train  of  gearing  so 


FIG.  15 

Combined  gasoline  pump  and  gravity 
gasoline  feed  to  engine. 


GAS  AND   OIL   ENGINE   HAND-BOOK       61 

large  and  heavy  that  it  absolutely  precludes  the 
possibility  of  making  any  reasonable  construction. 
When,  however,  the  engine  develops  the  same 
power  in  two  cylinders  with  impulses  twice  as 
frequent  and  only  one-half  as  strong,  it  is  possible 
to  make  a  train  of  gears  which  will  transmit  the 
full  power  of  the  engine  and  consequently  a 
strong  and  successful  gasoline  traction  engine. 
The  builders  of  gasoline  traction  engines  have 
heretofore  used  engines  of  the  old  models,  and 
while  these  engines  have  served  their  purpose  in 
stationary  work  and  to  some  extent  in  portable 
work,  their  use  has  not  been  as  satisfactory  as 
with  the  two-cylinder  style  of  gasoline  traction 
engine. 

Gas  or  Oil  Engines,  Successful  Operation  of. 
Gas  or  oil  engines  are  dependent  for  successful 
operation  on  two  things:  First,  a  charge  of  gas 
or  vapor,  mixed  with  sufficient  air  to  produce  an 
explosive  mixture,  and  second,  a  method  of  firing 
the  charge  after  it  has  been  taken  into  the  com- 
bustion chamber  of  the  motor.. 

When  coal  or  natural  gas  is  used  the  supply  is 
taken  from  the  main  and  mixed  directly  with  the 
necessary  proportion  of  air.  When  gasoline  or 
kerosene  is  used,  air  is  mixed  with  them  in  the 
correct  proportion  by  carbureting  devices. 

The  principal  parts  of  a  gas  or  oil  engine  are 
the  cylinder,  the  piston,  the  piston-rings  which 
fit  into  grooves  in  the  piston:  two  sets  of  valves, 


62       GAS  AND  OIL  ENGINE   HAND-BOOK 

one  to  admit  the  charge  and  the  other  to  permit 
it  to  escape  after  the  explosion,  a  crank  shaft  and 
connecting-rod  which  connect  it  with  the  piston, 
and  a  flywheel,  whose  presence  insures  steady 
running  of  the  motor,  and  whose  further  func- 
tions will  be  better  understood  as  the  descrip- 
tion proceeds.  In  the  two-cycle  form  of  gas  or 
oil  engine  there  is  really  but  one  valve,  which  is 
located  in  the  crank  case,  the  exhaust  and  admis- 
sion-ports being  covered  and  uncovered  by  the 
piston  itself. 

Generator.  This  term  is  usually  applied  to 
any  form  of  chemical  or  mechanical  energy  which 
can  be  used  to  produce  a  current  of  electricity. 
Mechanical  generators  of  electricity  used  for 
ignition  purposes  are  of  two  forms,  dynamos  or 
magnetos.  The  former  is  self-exciting  by  means 
of  coils  of  wire  wound  upon  the  magnet  limbs. 
The  latter  has  permanent  magnets  instead  of 
coils  of  wire  to  induce  the  current  in  the  arma- 
ture of  the  magneto.  Magnetos,  on  account  of 
their  simplicity  of  construction  and  low  first  cost, 
are  more  generally  used  for  ignition  purposes 
than  dynamos.  They  may  be  operated  by  the 
engine  with  a  friction-pulley,  gear  or  belt. 

Governing  Gas  or  Oil  Engines.  There  are 
various  methods  of  governing,  which  are  here 
enumerated  and  described. 

Hit-or-miss  principle:  Shutting  off  the  gas  or 
oil  supply,  opening  or  closing  the  exhaust,  shut- 


GAS  AND   OIL  ENGINE   HAND-BOOK       63 

ting  off  the  ignition,  disengaging  the  valve 
operator. 

Throttling  method:  Throttling  the  gas  or  oil 
supply,  throttling  the  charge  of  explosive  mix- 
ture. 

Varying  the  point  of  ignition:  In  cases  where 
gas  or  oil  engines  are  fitted  with  some  form  of 
electrical  ignition,  they  are  sometimes  regulated 
by  the  governor  being  connected  with  a  commu- 
tator, which  automatically  cuts  the  current  off 
from  the  sparking  device  when  the  limit  of  speed 
has  been  passed,  and  the  charge  is  not  exploded 
till  the  revolutions  of  the  engine  are  reduced  to 
the  proper  speed,  when  the  action  of  the  governor 
closes  the  electrical  circuit  and  the  ignition  again 
takes  place. 

A  similar  result  may  be  attained  also  by  vary- 
ing the  point  of  ignition,  but  both  of  these 
methods  are  not  very  economical. 

Figure  16  shows  a  form  of  governor  which 
operates  by  preventing  the  exhaust-valve  from 
opening.  When  the  speed  of  the  engine  passes 
its  normal  limit,  the  balls  A  of  the  governor 
move  out  towards  the  periphery  of  the  gear  or 
wheel  which  carries  them,  causing  the  cam  B  to 
be  moved  to  the  right  by  the  action  of  the  dogs 
on  the  governor  arms,  which  engage  in  a  grooved 
collar  on  the  sleeve  C. 

The  nose  of  the  cam  B  is  thus  kept  out  of 
engagement  with  the  roller  D  until  the  motor 


64       GAS  AND   OIL  ENGINE   HAND-BOOK 

resumes  its   normal  speed,   thus   preventing    the 
valve-lifter  from  opening  the  valve. 

Normally  the  cam  is  held  in  position  by  the 
springs  attached  to  the  governor  balls,   against 


FIG.  16 

Exhaust-valve  governor  which  operates  by  throwing  the  cam  out 
of  contact  with  the  cam-roller. 


the  shoulder  of  the  bearing  F,  which  carries  the 
cam-shaft  G. 

A  form  of  governor  is  shown  in  Figure  17 
which  may  be  used  in  connection  with  any  of  the 
methods  of  governing  described  above.  It  is 


GAS  AND  OIL  ENGINE   HAND-BOOK       65 


usually  located  on  an  independent  bracket  and 
driven  from  the  cam-shaft  of  the  motor. 

Figure  18  shows  a  governor  working  on  the 
hit-and-miss  principle.  When  the  engine  tends  to 
run  above  its 
normal  speed, 
the  action  of  the 
governor  balls 
causes  knife- 
edge  to  move 
away  from  the 
notch  in  the  end 
of  the  valve 
plunger,  thus 
throwing  the 
valve  out  of  ac- 
tion. 

An  inertia 
governor  is 
shown  in  Figure 
19.  Should  the 
engine  attempt 
to  increase  its  FIG.  17 

,     .  Centrifugal  governor  for  operating  either 

speed  above  nor-         hit-and-miss  or  throttling  forms  of 
speed  regulating  mechanism. 

mal,    the    lower 

end  of  the  double-ended  lever,  at  the  left 
in  the  drawing,  will  be  depressed  by  the  cam 
and  the  valve-lifter  thrown  out  of  an  engage- 
ment with  the  step  immediately  above  the  roller, 
in  this  manner  preventing  any  further  action  of 


66        GAS  AND   OIL   ENGINE   HAND-BOOK 

the  valve-lifter  until  the  speed  of  the  motor  is 
reduced. 

Hand  Starting  Device.  A  hand  starting 
device,  for  starting  engines  of  from  10  to  25 
horsepower,  is  shown  in  Figure  20,  the  flywheels 
of  the  engine  are  turned  over  until  the  piston  is 
just  past  the  dead  center  of  the  explosion  or 
power  stroke,  the  combustion  chamber  is  filled 
with  an  explosive  mixture  by  means  of  a  hand 


1303 


FIG.  18 

Hit-and-miss  type  of  centrifugal  governor  which  operates  by 

throwing  the  knife-edge  out  of  contact  with  the 

valve-stem  lifter. 


pump,  after  a  match  has  been  inserted  in  the  cock 
shown  to  the  left  in  the  drawing.  The  plug  of 
the  cock  is  closed,  cutting  off  the  match,  the 
plunger  is  given  a  smart  blow  with  the  hand,  the 
match  is  then  consequently  fired,  the  charge 
ignited  and  the  piston  started  on  its  working  or 
power  stroke. 

Horsepower  of  Gas  or  Oil  Engines.    A  horse- 
power is  the  rate  of  work  or  energy  expended  in 


GAS  AND   OIL  ENGINE   HAND-BOOK       67 


raising  a  weight  of  550  pounds  one  foot  in  one 
second,  or  raising  33,000  pounds  one  foot  in  one 
minute.  This  is  far  more  work  than  the  average 
horse  can  do  for  any  great  length  of  time. 
A  good  horse  for 
a  short  period  of 
time  can  do 
much  more. 

As  the  ordi- 
nary formula 
used  for  the  cal- 
culation  of 
horsepower  i  n 
connection  with 
steam  engines  is 
not  directly  ap- 
plicable to  gas  or 
oil  engine  prac- 
t  i  c  e,  formulas 
are  here  given 
that  are  more 
suited  to  the  pur- 
pose. 

Let   D   be   the   diameter  of   the   cylinder  in 
inches,   and  S  the  stroke  of  the  piston  also  in 
inches:  if  N  be  the  number  of  revolutions  per 
minute  of  the  motor,  and  H.P  the  required  horse- 
power of  the  motor,  then  for  a  four-cycle  motor 
D2XSXN 
18.000 


FIG.  19 

Inertia  type  of  governor,  which  operates 

by  throwing  the  valve-lifter  rod  out  of 

contact  with  the  cam-roller  lever. 


68       GAS  AND  OIL  ENGINE  HAND-BOOK 


Example:     What  horsepower  should  be  devel- 
oped by  an  engine  of  4j  inches  bore  and  6  inches 
stroke,  at  a  speed  of  600  revolutions  per  minute? 
Answer:     The  square  of  the  bore  multiplied 

by  the  stroke  is 
equal  to  121.5, 
this  multiplied 
by  600,  and  di- 
vided by  18,000, 
gives  4.05  as 
the  horsepower 
of  the  motor. 

From  a  theo- 
retical stand- 
point a  two- 
cycle  engine 
should  not  only 
have  as  great  a 
speed  but  also  be 
capable  of  de- 
veloping almost 
;  power 

that  a  four-cycle 
engine  does.  It  is  a  fact,  nevertheless,  that  its 
actual  performance  is  far  different. 

The  horsepower  of  a  two-cycle  engine  may  be 
calculated  from  the  following  formula: 
D2XSXN 

21,000 
Example:     Required,    the    horsepower    of    a 


FIG.  20 

Match  Igniter  for  starting  gas  or  gasoline    twjce 


GAS  AND   OIL   ENGINE   HAND-BOOK       G9 

two-cycle  motor  of  4j  inches  bore  and  6  inches 
stroke,  with  a  speed  of  600  revolutions  per  minute? 

Answer:  The  square  of  the  bore  multiplied 
by  the  stroke  is  equal  to  121.5,  which  multiplied 
by  600,  and  divided  by  21,000,  gives  3.47  as  the 
required  horsepower.  The  results  given  by  the 
above  examples  agree  very  closely  with  those 
obtained  from  actual  practice. 

Indicated  horsepower  is  the  actual  power  pro- 
duced in  the  cylinder,  from  which  must  be 
deducted  the  power  required  for  driving  the 
engine  itself. 

Brake  horsepower,  also  called  actual  horse- 
power, is  the  net  effective  power  given  off  at 
the  driving  pulley  of  the  engine,  and  this  form  of 
horsepower  is  the  one  for  which  a  guarantee 
should  be  obtained  from  manufacturers  by  users. 

Hot  Tube  Ignition.  The  incandescent  tube 
system  of  ignition  consists  of  a  tube  of  metal  or 
porcelain,  one  end  of  which  is  closed  and  the 
other  screwed  or  fastened  into  the  combustion 
chamber  by  suitable  means.  - 

The  flame  of  a  Bunsen  burner  is  projected 
a,gainst  the  ignition  tube,  rendering  it  incandescent, 
resulting  in  the  firing  of  the  compressed  charge 
slightly  before  the  end  of  the  compression  stroke. 

The  Bunsen  burner  should  be  adjusted  so  as 
to  give  a  small  blue  flame  entirely  round  the 
ignition  tube.  If  too  much  gas  is  being  used,  a 
smell  will  come  from  the  chimney. 


70       GAS  AND  OIL  ENGINE  HAND-BOOK 

It  is  important  that  the  ignition  tube  be  always 
kept  to  a  bright  red  heat,  should  it  be  allowed  to 
get  foul,  misfires  will  occur. 

Ignition  tubes  should  be  renewed  as  soon  as 
they  begin  to  appear  defective,  which  will  be 
indicated  by  irregularity  in  the  firing,  as, 
although  the  engine  may  continue  working  for 
some  time,  a  considerable  loss  of  gas  may  be 
going  on. 

In  putting  in  a  new  ignition  tube  care  should 
be  taken  that  no  grit  is  allowed  to  get  into  the 
passage  leading  to  the  combustion  chamber. 

Igniter,  Cleaning  an.  The  igniter  should  be 
taken  off  and  cleaned  after  intervals  of  from  sixty 
to  ninety  days  of  constant  running.  All  carbon 
and  corrosion  should  be  removed  from  the  igniter 
points  and  mica  washers. 

Ignition,  Catalytic.  This  method  of  ignition 
for  gas  or  oil  engines  is  based  on  the  property 
possessed  by  spongy  platinum  of  becoming  incan- 
descent when  in  contact  with  coal  gas  or  car- 
bureted air.  With  this  means  of  ignition,  speed 
regulation  or  variation  can  only  be  had  within 
very  narrow  limits.  The  principal  objections  to 
its  extended  use  are,  danger  of  premature  ignition, 
lack  of  speed  control  and  difficulty  of  starting  the 
motor. 

Ignition,  Forms  of.  The  earlier  forms  of  gas 
engines  built  had  the  compressed  charge  ignited 
by  means  of  a  flame,  which  has,  however,  now 


GAS  AND  OIL  ENGINE  HAND-BOOK       71 

given  place  to  the  three  following  methods  of 
ignition : 

Hot  surface. 

Hot  tube. 

Electric. 

The  first-named  form  of  ignition  is  illustrated 
in  Figure  26.  In  this  form  the  heated  walls 
of  the  vaporizer  act  as  the  igniter,  aided  by  the 
heat  generated  during  the  compression  of  the 
gases.  The  chamber  being  first  heated,  after- 
ward the  proper  temperature  is  maintained  by 
the  heat  caused  by  the  combustion  of  the  gases. 
Various  other  devices  in  which  heat  is  maintained 
to  cause  self  or  spontaneous  ignition  are  now 
made. 

The  second  type,  that  of  the  hot  tube,  is 
shown  in  Figure  12  at  P.  This  form  of  ignition 
consists  of  a  metal  tube  fitted  into  the  vapor- 
izer or  cylinder  wall.  It  is  closed  at  one  end, 
the  other  end  being  open  to  the  cylinder.  It 
is  heated  by  a  Bunsen  flame  over  part  of  its 
length.  When  compression  due  to  the  inward 
stroke  of  the  piston  takes  place  in  the  cylinder 
the  explosive  mixture  is  compressed  into  the  tube 
and  is  ignited  by  coming  in  contact  with  the 
heated  portion  of  it.  Nickel-steel  tubes  are 
preferable  to  wrought  iron,  although  both  are 
used  for  this  purpose. 

The  third  form,  that  of  electric  ignition,  is  of 
two  kinds,  the  primary  make  and  break,  with 


72       GAS  AND   OIL  ENGINE   HAND-BOOK 


which  a  mechanical  device  to  make  the  primary 
circuit  in  the  combustion  chamber  of  the  motor  is 
used,  and  the  secondary  or  jump-spark  form  of 
ignition,  in  which  the  spark  jumps  or  arcs  within 
the  cylinder  without  the  aid  of  any  mechanical 
device. 

Ignition  Mechanism.  A  form  of  ignition 
mechanism  used  in  connection  with  the  primary 
make  and  break  system  of  electrical  ignition  is 

i  1 1  u  s  t  r  a  ted  in 
Figure  21.  Up- 
on the  operating 
rod  being  moved 
to  the  left,  the 
pawl  carried  by 
the  upper  arm 
of  the  bell-crank 
lever  forces 
downward  the 
small  trigger 
carried  upon  the 
outer  end  of  the 

movable  electrode  and  in  this  manner  passes 
by  it.  Upon  the  return  stroke  of  the  operating 
rod  the  upper  end  of  the  pawl  engages  with  the 
trigger,  bringing  the  contact-points  of  the  movable 
and  fixed  electrode  together  for  a  short  period  of 
time.  A  further  movement  of  the  operating  rod 
in  the  same  direction  causes  the  trigger  to  be 
released  from  contact  with  the  pawl.  This 


FIG.  21 

Ignition  mechanism  for  use  in  connection 
with  a  primary  make  and  break  spark. 


GAS  AND  OIL  ENGINE  HAND-BOOK       73 

action  causes  the  contact-points  of  the  electrodes 
to  suddenly  fly  apart  and  a  spark  or  arc  is  pro- 
duced between  them. 

Ignition,  Reason  for  Advancing  Point  of. 
It  may  be  well  to  explain,  without  entering  into 
theoretical  details,  that  when  an  engine  is  running 
at  normal  speed  the  ignition  mechanism  is  so  set 
that  ignition  takes  place  slightly  before  the  piston 
reaches  the  end  of  its  compression  stroke. 

If  the  charge  is  fired  at  or  after  the  end  of  the 
compression  stroke,  the  average  pressure  on  the 
piston,  and  consequently  the  power,  is  decreased 
in  proportion.  Therefore  to  ensure  perfect  com- 
bustion with  a  maximum  pressure  at  the  com- 
mencement of  the  explosion  stroke,  the  point  of 
ignition  must  be  earlier,  and  advance  as  the 
speed  increases. 

Indicator  Diagrams.  The  thermal  or  heat 
efficiency  of  a  gas  or  oil  engine  may  be  deter- 
mined from  an  indicator  diagram,  which  gives  a 
representation  of  the  internal  conditions  through- 
out the  entire  cycle  of  operations.  The  diagram 
tells  many  things  essential  to  be  known. 

It  gives  the  initial  explosive  pressure,  or  the 
pressure  a  moment  after  ignition  has  taken  place. 
It  shows  whether  the  volume  of  the  charge  is 
diminished  during  the  period  of  admission.  It 
gives  the  point  of  ignition,  when  the  ignition  is 
complete  and  when  expansion  begins.  It  indi- 
cates the  pressure  of  expansion  during  the  work- 


74        GAS  AND   OIL  ENGINE  HAND-BOOK 

ing  stroke.  It  gives  the  terminal  pressure  when 
the  exhaust  is  opened.  It  shows  the  rapidity  of 
the  exhaust.  It  indicates  the  back-pressure  on 
the  piston,  due  to  the  exhaust.  It  shows  the 
point  of  opening  of  the  exhaust.  It  gives  the 
mean  power  used  in  driving  the  motor.  It  also 
indicates  any  leakage  of  valves  or  piston. 

The  usual  method  of  ascertaining  the  area  of 
an  indicator  diagram  is  by  means  of  an  instru- 
ment known  as  a  planimeter,  which  is  used  to 
calculate  the  area  of  any  irregular  surface,  by 
moving  a  tracing  point  attached  to  the  instru- 
ment over  the  entire  irregular  boundary  line  of 
the  figure. 

But  for  the  purpose  of  ascertaining  the  horse- 
power of  an  engine  it  will  be  sufficiently  accurate 
to  illustrate  the  principles  involved,  to  calculate 
the  area  of  the  diagram  by  means  of  ordinates  or 
vertical  measurements. 

The  upper  drawing  in  Figure  22  represents  a 
card  taken  from  an  engine  of  4  inches  bore  and 
6  inches  stroke,  at  600  revolutions  per  minute, 
and  under  a  full  load.  The  diagram  is  divided 
into  12  parts  as  shown  by  vertical  lines,  the 
lengths  of  which  are  in  terms  of  the  spring, 
which  is  100.  Then  1.90+1.36+1.00,  etc., 
divided  by  12,  equals  0.665  as  the  average  height 
of  the  diagram.  Its  length  is  6  inches,  as  shown, 
therefore  the  area  of  the  card  is  approximately 
3.99  square  inches.  As  the  initial  explosive  force 


GAS  AND   OIL  ENGINE  HAND-BOOK       75 

from  the  diagram  is  250  pounds  per  square  inch, 
and  a  100  indicator  spring  used,  the  height  of 
the  card  is  250  divided  by  100,  which  equals 
2j  inches  as  the  height  of  the  card.  The  mean 
effective  pressure  on  the  piston  in  pounds  per 


FIG.  22 

Indicator  diagrams,  showing  cards  with  engine  at  full  and 
at  half  load. 


square  inch  will  therefore  be  equal  to  the  area  of 
the  diagram  3.99,  divided  by  the  area  of  the 
whole  card,  which  is  2jX  6,  equals  15,  and  multi- 
plied by  250,  the  initial  explosive  force,  or 
3.99X250,  and  divided  by  15,  equals  66.5  pounds 


76       GAS  AND   OIL  ENGINE  HAND-BOOK 

per  square  inch  as  the  mean  effective  pressure 
required. 

From  this  the  indicated  horsepower  of  the 
engine  can  readily  be  found  as  follows: 

Let  M.P  be  the  mean  effective  pressure  in 
pounds  per  square  inch,  A  the  area  of  the  cylin- 
der in  square  inches,  S  the  stroke  of  the  piston  in 
inches,  N  the  number  of  explosions  per  minute, 
and  H.P  the  indicated  horsepower,  then 

_  M.P  x  A  x  S  x  N 
H.P  — 


396,000 
66.5  X  12.56  X  6  X  300 
396,000 


=  3.79 


as  the  required  indicated  horsepower  of  the 
engine.  The  indicated  horsepower  of  any  engine 
will  always  be  greater  than  that  obtained  from  a 
brake  test,  as  it  simply  represents  the  actual 
thermo-dynamic  (heat-pressure)  conditions  within 
the  cylinder,  and  takes  no  account  of  friction  and 
other  external  losses. 

The  lower  drawing  in  Figure  22  is  a  card 
taken  from  the  same  engine  running  under  half 
load. 

Indicator,  Use  of  the.  An  indicator  consists 
of  a  cylinder  within  which  works  a  piston  under 
the  tension  of  a  helical  spring  of  predetermined 
strength.  The  rod  attached  to  the  piston  carries 
a  pivoted  arm  which  works  on  a  horizontal  lever. 
This  lever  carries  a  pencil  bearing  against  a 


GAS  AND  OIL  ENGINE  HAND-BOOK       77 

drum.  This  drum  is  so  arranged  with  a  spring 
that  it  may  be  partially  rotated  by  the  pull  on  an 
attached  string.  A  sheet  of  paper  is  wound  on 
the  drum  and  held  in  place  by  spring  clips.  The 
pressure  in  the  cylinder  acting  on  the  spring 
causes  the  pencil  to  mark  the  paper,  the  indicator 
card  or  diagram  being  traced  by  the  forward  and 
backward  movement  of  the  drum. 

Inspecting  Gas  or  Oil  Engines.  Before 
examining  an  engine  with  a  light,  care  should  be 
taken  that  the  combustion  chamber  is  free  from 
gas  mixture.  This  can  be  done  by  turning  the 
engine  round  a  few  times.  The  ignition  should 
be  cut  out  and  the  fuel  supply  cock  closed.  It  is 
more  or  less  dangerous  to  look  down  the  chimney 
of  the  ignition  tube  when  the  engine  is  running. 

It  is  sometimes  necessary  to  inspect  the  interior 
of  the  engine  cylinder  with  a  lighted  candle,  for 
the  purpose  of  locating  some  sharp  projection, 
burnt  carbon,  crack  or  sand  hole,  etc.  When 
doing  this,  always  remember  that  a  charge  of 
fuel  may  remain  in  the  cylinder,  and  whether  the 
candle  is  inserted  through  one  of  the  valve  ports 
or  the  open  end  of  the  cylinder,  be  sure  to  keep 
the  face  away  from  the  opening. 

Installing  a  Gas  or  Oil  Engine.  Secure  the 
engine  to  a  good  foundation  made  according  to 
the  plans  furnished  by  the  engine  builder. 

Set  up  the  water  tank  at  any  convenient  dis- 
tance from  the  engine,  preferably  as  close  as 


78        GAS  AND  OIL  ENGINE  HAND-BOOK 

possible  on  the  exhaust  side.  Use  short  pieces 
of  rubber  hose  in  the  cooling  tank  piping.  Put 
the  shut-off  valve  close  to  the  tank.  Be  sure  that 
the  vent  pipe  is  long  enough  to  be  above  the  top 
of  the  tank.  Water  should  always  be  at  least 
6  inches  above  the  upper  pipe  or  it  will  not 
circulate. 

The  water  tank  may  be  dispensed  with  by 
connecting  a  water  feed  pipe  direct  from  a 
hydrant  to  the  opening  in  exhaust  valve  chamber 
and  running  a  waste  pipe  from  top  of  cylinder 
jacket  to  carry  off  the  water. 

Regulate  the  amount  of  water  by  means  of  a 
stopcock  placed  in  this  pipe. 

Keep  the  cylinder  jacket  just  as  hot  as  can  be 
borne  by  the  hand,  say  from  140  to  160  degrees 
Fahrenheit. 

The  fuel  tank  may  be  placed  outside  of  the 
building  and  should  be  in  a  vertical  position, 
twelve  to  eighteen  inches  lower  than  the  top  of 
the  foundation,  so  that  the  fuel  will  flow  from 
engine  to  tank.  Care  should  be  taken  to  wash 
out  every  piece  of  pipe  with  gasoline  before  con- 
necting up,  this  removes  all  dirt  and  scale  which 
would  interfere  with  the  proper  working  of  the 
check  valves.  Extra  care  should  be  taken  in 
making  all  water  and  fuel  pipe  connections 
tight.  Use  soap  in  the  joints  of  the  fuel  pipes. 

Run  the  exhaust  pipe  in  any  convenient  direc- 
tion, placing  the  muffler  as  near  the  engine  as 


GAS  AND   OIL   ENGINE   HAND-BOOK       79 

possible.  Never  use  a  pipe  smaller  than  the 
opening  in  the  muffler.  Long  and  crooked  runs 
should  be  avoided,  but  if  necessary  use  a  size 
larger  pipe  It  is  not  advisable  to  exhaust  into 
a  chimney. 

Long  vertical  pipes  collect  water  and  should 
be  connected  with  a  Tee  fitting  at  the  bottom 
provided  with  suitable  connections  for  draining. 

Connect  the  battery  cells  with  the  spark  coil, 
switch  and  binding  posts  on  the  engine.  The 
ends  of  wires  where  the  connections  are  made 
should  have  all  the  insulation  removed  and  all 
nuts  tightened  well  to  insure  good  connections. 

Jump-spark  Wiring  Diagram.  A  method  of 
wiring  for  a  single  cylinder  engine  using  a  set  of 
batteries  and  a  magneto-generator  is  illustrated 
in  Figure  23.  By  moving  the  switch-finger, 
either  the  magneto-generator  or  the  battery  may 
be  used  as  desired,  or  both  cut  out. 

Knocking  or  Pounding  in  an  Engine.  May 
be  due  to  any  of  the  following  causes: 

Premature  ignition:  The  sound  produced  by 
premature  ignition  may  be  described  as  a  deep, 
heavy  pound. 

Using  a  poor  grade  of  lubricating  oil  will  cause 
premature  ignition.  The  carbon  from  the  oil 
will  deposit  on  the  head  of  the  piston  in  cakes 
and  lumps,  and  will  not  only  increase  the  com- 
pression but  will  get  hot  after  running  a  short 
time  and  will  ignite  the  charge  too  early,  and 


80        GAS  AND  OIL   ENGINE   HAND-BOOK 


GAS  AND  OIL  ENGINE  HAND-BOOK       81 

thereby  produce  the  same  effect  as  advancing  the 
spark  too  much.  If  this  is  the  cause  the  pound- 
ing will  cease  as  soon  as  the  carbon  deposit  is 
removed  from  the  combustion  chamber. 

Badly  worn  or  broken  piston-rings. 

Improper  valve  seating. 

A  badly  worn  piston. 

Piston  striking  some  projecting  point  in  the 
combustion  chamber. 

A  loose  wrist-pin  in  the  piston. 

A  loose  journal-box  cap  or  lock-nut. 

A  broken  spoke  or  web  in  the  flywheel. 

Flywheel  loose  on  its  shaft. 

If  the  sparking  device  be  placed  so  as  to  be 
exactly  in  the  center  of  the  combustion  space  an 
objectionable  knock  occurs,  which  has  never 
been  fully  explained.  In  some  engines  it  renders 
a  particular  position  of  the  ignition  unusable, 
this  form  of  knock  disappears  either  on  making 
a  slight  advance  or  retardation  of  the  ignition. 

If  the  cylinder  is  in  good  condition,  and  a 
bumping  noise  is  heard  when  working  at  full 
load,  it  may  arise  from  too  much  oil  being  sup- 
plied to  the  engine,  which  should  be  regulated 
accordingly. 

Explosions  occurring  during  the  exhaust  or 
admission  stroke.  This  is  almost  always  due  to 
a  previous  misfire,  and  it  may  be  prevented  by 
stopping  the  misfires. 

If  the  ignition  is  so  timed  that  the  gases  reach 


82        GAS  AND   OIL  ENGINE   HAND-BOOK 

their  full  explosion  pressure  during  the  compres- 
sion stroke,  that  is,  if  the  spark  be  unduly 
advanced,  an  ugly  knock  occurs,  and  great  pres- 
sure is  developed  on  the  crank-pin  bearing,  wrist 
pin,  and  connecting-rod.  The  effect  may  be  the 
bending  or  distorting  of  the  connecting-rod. 

The  crank-pin  may  not  be  at  right  angles  to 
the  connecting-rod.  This  cause  of  knock  is  often 
hard  to  find. 

The  bearings  at  either  end  of  connecting-rod 
may  be  loose.  A  knock  during  the  explosion 
stroke,  and  also  at  each  reversal  of  the  direction 
of  the  piston. 

If  the  crank  shaft  is  not  perfectly  at  right 
angles  to  the  connecting-rod,  the  crank  shaft  and 
flywheels  will  travel  sideways  so  as  to  strike  the 
crank  shaft  bearings  on  one  side  or  the  other. 

Liquid  Fuels.  The  supply  of  petroleum  is 
produced  chiefly  in  the  United  States  of  America 
and  in  Russia,  while  it  is  also  found  in  many 
other  countries  in  small  quantities. 

Petroleum  is  found  in  the  United  States  in  the 
Central  Eastern  States,  but  principally  in  Penn- 
sylvania, New  York,  Ohio  and  West  Virginia,  in 
Texas  in  the  region  around  Beaumont  and  Cor- 
sicana,  in  California  chiefly  in  the  Kern  County, 
Coalinga,  Los  Angeles,  producing  fields.  In 
Russia,  oil  fields  are  found  around  Baku  and  in 
the  range  of  the  Caucasus  Mountains. 

Kerosene  or  shale  oil,  a  liquid  fuel  produced 


GAS  AND   OIL  ENGINE  HAND-BOOK       83 

by  a  slow  process  of  distillation  of  shale  and 
bituminous  coal,  is  also  produced  in  Scotland. 

Crude  petroleum  as  it  issues  or  is  pumped 
from  the  earth  contains  a  variety  of  hydrocarbons 
of  different  characteristics,  and  after  its  sediment 
has  settled  it  is  subjected  to  a  process  of  refining 
known  as  fractional  distillation,  by  which  process 
the  various  hydrocarbons  are  separated  and  are 
afterwards  condensed  into  the  different  products 
known  in  commerce  as  benzine,  gasoline,  naph- 
tha, being  the  lighter  products,  having  a  flash- 
point below  73  degrees  Fahrenheit.  Next  the 
illuminating  oils,  such  as  W»  W.  150  degree 
kerosene,  White  Rose  and  other  brands  of  a 
similar  composition,  are  obtained,  having  a  flash- 
point above  73  degrees  Fahrenheit.  The  next 
product  is  gas  oil,  or  fuel  oil,  used  largely  for 
gas-making  and  also  as  fuel  in  gas  and  oil 
engines,  having  a  flash-point  of  about  190  degrees. 
Lubricating  oils,  paraffine,  wax  and  vaseline  are 
afterwards  procured,  the  residue  being  a  heavy 
liquid  sometimes  used  for  fuel. 

Locating  an  Engine.  The  engine  should  be 
placed  in  a  separate,  well-lighted  room  if  possible 
and  free  from  the  dust  of  the  shop  or  factory.  At 
least  three  feet  of  space  should  be  provided  round 
the  engine  to  enable  the  operator  to  get  at  the 
flywheel  and  other  working  parts,  and  it  should 
be  arranged  so  as  to  give  a  straight  and  fairly 
long  belt  drive. 


84       GAS  AND  OIL  ENGINE  HAND-BOOK 

Lubricants.  To  ensure  easy  running  and 
reduce  the  element  of  friction  to  a  minimum  it  is 
absolutely  necessary  that  all  such  parts  should 
be  supplied  with  oil  or  lubricating  grease, 
but  it  is  also  a  fact,  not  so  well  understood, 
that  different  kinds  of  lubricant  are  necessary  to 
the  different  parts  or  mechanisms  of  an  explosive 
motor. 

As  the  cylinder  of  a  gas  or  oil  engine  operates 
under  a  far  higher  temperature  than  is  possible 
in  a  steam  engine,  consequently  the  oil  intended 
for  use  in  these  cylinders  must  be  of  such  quality 
that  the  point  at  which  it  will  burn  or  carbonize 
from  heat  is  as  high  as  possible. 

While  a  number  of  animal  and  vegetable  oils 
have  a  flashing-point,  and  yield  a  fire  test  suffi- 
ciently high  to  come  within  the  above  require- 
ments, they  all  contain  acids  or  other  substances 
which  have  a  harmful  effect  on  the  metal  surfaces 
it  is  intended  to  lubricate. 

The  general  qualities  essential  in  a  lubricating 
oil  for  use  in  gas  or  oil  engine  cylinders  include  a 
flashing-point  of  not  less  than  360  degrees 
Fahrenheit,  and  fire  test  of  at  least  420  degrees, 
together  with  a  specific  gravity  of  25.8. 

At  350  to  400  degrees  Fahrenheit,  lubricating 
oils  are  as  fluid  as  kerosene,  therefore  the  adjust- 
ment of  the  feed  should  be  made  when  the  lubri- 
cator and  its  contents  are  at  their  normal  heat. 
Steam  engine  oils  are  unsuitable  for  the  dry  heat 


GAS  AND  OIL  ENGINE  HAND-BOOK       85 

of  motor  cylinders  in  which  they  are  decomposed 
whilst  the  tar  is  deposited. 

All  oils  will  carbonize  at  .500  to  600  degrees 
Fahrenheit,  but  graphite  is  not  affected  by  over 
2,000  degrees  Fahrenheit,  which  is  the  approxi- 
mate temperature  of  the  burning  gases  in  an 
explosive  engine.  The  cylinder  of  these  engines 
may  attain  an  average  temperature  of  300  to 
400  degrees  Fahrenheit.  So  that  graphite  would 
be  very  useful  if  it  could  be  introduced  into  the 
engine  cylinder  without  danger  of  clogging  the 
valves  and  could  be  fed  uniformly.  These  diffi- 
culties have  not  yet  been  overcome. 

The  film  of  oil  between  a  shaft  and  its  bearing 
is  under  a  pressure  corresponding  to  the  load  on 
the  bearing,  and  is  drawn-  in  against  that  pres- 
sure by  the  shaft.  It  might  not  be  thought 
possible  that  the  velocity  of  the  shaft  and  the 
adhesion  of  the  oil  to  the  shaft  could  produce  a 
sufficient  pressure  to  support  a  heavy  load,  but 
the  fact  may  be  verified  by  drilling  a  hole  in  the 
bearing  and  attaching  a  pressure  gauge. 

Lubrication  of  Oil  Engine  Cylinders.  On 
account  of  the  rapid  decomposition  of  the  lubri- 
cating oil  in  gasoline  and  kerosene  engine  cylin- 
ders, it  is  very  important  that  an  oil  should  be 
selected  which  does  not  vaporize  or  carbonize 
easily  and  leave  much  residue.  A  pressure  sight- 
feed  lubricator  should  be  employed,  and  no  more 
lubricating  oil  used  than  is  absolutely  necessary. 


86        GAS  AND  OIL   ENGINE  HAND-BOOK 

For  some  reason  gasoline  and  kerosene  engines 
give  more  trouble  in  this  connection  than  gas 
engines.  One  reason  is  that  the  hydrocarbon 
vapor  of  an  oil  engine  affects  the  lubricating  oil 
in  a  different  manner  to  the  explosive  mixture  of 
a  gas  engine. 

Lubrication,  Over  or  Improper.  Smoke 
coming  from  the  exhaust  of  a  gas  or  oil  engine  is 
due  to  one  of  two  conditions :  Over- lubrication — 
too  much  lubricating  oil  being  fed  to  the  cylinder 
of  the  engine — or  too  rich  a  mixture,  that  is,  too 
much  gasoline  and  an  insufficient  supply  of  air. 

The  first  condition  may  be  readily  detected  by 
the  smell  of  burned  oil  and  a  yellowish  smoke. 
The  second,  by  a  dense  white  smoke  accom- 
panied by  a  pungent  odor. 

If  the  engine  is  working  properly,  the  exhaust 
should  be  almost  colorless  or  with  a  light  blue 
haze.  The  oil  used  should  be  of  the  highest  flash- 
point obtainable,  as  the  heat  in  a  gas  or  oil 
engine  cylinder  is  very  dry  and  intense. 

The  effect  upon  animal  or  vegetable  oils  of 
such  heat  would  be  to  partially  decompose  the 
oils  into  stearic  acids  and  oleic  acid  and  the  con- 
version of  these  into  pitch. 

Mineral  oils  are  not  so  readily  decomposed  by 
heat,  but  at  their  boiling  points  they  are  con- 
verted into  gas,  and  any  oil,  the  boiling  point  of 
which  is  in  the  neighborhood  of  the  working 
temperature  of  the  engine  cylinder,  is  useless,  as 


GAS  AND  OIL  ENGINE   HAND-BOOK       87 

its  body  is  too  greatly  reduced  to  leave  an  effect- 
ive working  film  on  the  cylinder  walls. 

Lubricators.  Always  ascertain  from  the 
builder  of  the  engine  how  many  drops  of  oil  per 
minute  are  necessary  for  the  different  working 
parts  of  the  engine.  The  lubricators  or  oil  cups 
should  then  be  set  accordingly. 

It  should  be  remembered  that  in  cold  weather, 
when  the  oil  is  thick,  a  different  adjustment  of 
the  lubricators  will  be  necessary  from  that  found 
suitable  in  warm  weather.  It  is  important  that 
the  lubrication  should  be  regular,  and  good  oil 
used,  but  not  too  much.  Too  much  oil  will  foul 
the  igniter  points,  clog  the  valves,  and  interfere 
with  the  quality  of  the  explosive  mixture.  For 
this  reason  the  lubricators  should  always  be 
carefully  closed  when  the  engine  is  stopped.  If  a 
mechanical  lubricator  is  used,  examine  the 
mechanism  sometimes,  and  do  not  trust  entirely 
to  the  feed.  If  a  pressure  lubricator  is  used,  see 
that  the  piston  or  cap  is  tight,  for  if  not  the 
pressure  will  stop  the  lubrication. 

Magneto  Generator.  The  simplest  form  of 
magneto  consists  of  two  or  more  magnets  of 
horse-shoe  shape,  the  ends  of  which  embrace  the 
pole-pieces,  between  which  rotates  a  shuttle 
armature  wound  with  small  insulated  copper 
wire.  Rotation  of  the  armature  of  the  magneto 
tends  to  disturb  the  path  of  the  lines  of  force  or 
magnetic  flux  flowing  between  the  ends  of  the 


88        GAS  AND  OIL  ENGINE   HAND-BOOK 

permanent  magnets,  which  in  turn  set  up  power- 
ful induced  currents  in  the  armature.  The 
current  produced  by  the  magneto  is  of  an  alter- 
nating nature,  but  is  converted  into  a  direct  or 
continuous  current  by  means  of  the  commutator 
on  the  armature  shaft. 

Misfiring,  Causes  of.  Misfiring  means  failing 
to  fire  every  explosive  charge  that  the  engine 
takes. 

One  of  the  most  common  causes  of  misfiring 
is  an  improper  mixture  of  gasoline  and  air.  Too 
much  air  or  too  much  gasoline  will  cause  mis- 
firing. 

Batteries  which  are  almost  exhausted  will  give 
rise  to  explosions  in  the  engine  cylinder  which 
seem  all  the  more  violent  on  account  of  their 
irregularity.  It  is  perfectly  useless  to  connect  a 
set  of  nearly  exhausted  cells  with  a  new  set, 
either  in  series  or  parallel,  as  it  will  reduce  the 
new  cells  nearly  to  the  voltage  of  the  exhausted 
ones. 

Examine  the  battery  and  all  its  connections  at 
the  terminals,  and  determine  whether  the  battery 
is  exhausted  or  not,  or  whether  there  are  broken 
connections.  It  may  be  that  the  ignition  contact 
points  need  cleaning  or  attention  otherwise. 
Also  ascertain  whether  the  fuel  is  being  fed  to 
the  engine  in  proper  quantities.  It  may  not  be 
getting  enough  at  each  charge  or  perhaps  too 
much. 


GAS  AND   OIL  ENGINE   HAND-BOOK       89 


Misfiring  will  also  occur  from  the  ignition  tube 
being  fouled  from  soot  or  oil. 

Mixing  Valve.  For  stationary  or  portable 
gasoline  engines  where  the  speed  is  not  being 
constantly  changed,  mixing  valves  are  specially 


K 


FIG.  24 

Mixing  valve  for  use  with  gasoline  engine,  showing  air  inlet- valve 
and  gasoline  needle- valve  regulation. 

adapted.  A  standard  type  of  mixing  valve  is 
illustrated  in  Figure  24.  It  consists  of  a  chamber 
A,  valve  B,  spring  C,  collar  D,  valve-stem 
guide  E,  cover  F,  gasoline  inlet  G,  needle- 
valve  H,  thumb-nut  J  and  lock-spring  K. 

The  gasoline  is   fed  through  a  suitable  pipe 


90        GAS  AND   OIL  ENGINE  HAND-BOOK 

from  the  supply  tank  to  the  opening  in  the  seat 
of  the  valve.  The  rate  of  feed  or  flow  of  the 
gasoline  is  regulated  by  means  of  the  needle- 
valve.  The  inductive  action  of  the  engine  piston 
draws  the  valve  from  its  seat  and  at  the  same 
time  uncovers  the  opening  in  the  valve-seat  lead- 
ing from  the  gasoline  supply  pipe  and  allows  of 
the  flow  of  a  small  quantity  of  gasoline  as  the 
case  may  be. 

The  gasoline  mixes  with  the  air  drawn  through 
the  opening  in  the  valve-seat  and  the  friction  of 
passing  around  the  narrow  space  between  the 
valve  and  its  seat  insures  a  uniform  mixture  of 
gasoline  and  air.  The  air  is  drawn  through  the 
mixing  valve  in  the  direction  indicated  by  the 
arrows. 

Oil  Engine  Cycle.  The  cycle  or  series  of 
operations  which  take  place  in  the  vaporizing 
and  combustion  chambers  of  one  of  the  usual 
forms  of  oil  engine  is  illustrated  in  Figure  25. 
Before  starting  the  engine  the  vaporizing  chamber, 
shown  to  the  left  in  the  drawing,  is  brought  to  a 
red  heat  by  means  of  a  Bunsen  burner,  this  heat 
being  afterwards  maintained  by  the  combustion 
of  the  gases  in  the  vaporizing  chamber. 

During  the  suction  stroke  of  the  piston,  a  jet 
or  spray  of  oil  is  forced  through  the  opening  in 
the  nozzle  at  the  bottom  of  the  vaporizing  cham- 
ber by  means  of  a  pump,  and  upon  coming 
into  contact  with  the  hot  interior  of  the  chamber 


GAS  AND  OIL  ENGINE  HAND-BOOK       91 


is  at  once  transformed  into  vapor,  at  the  same 
time  a  charge  of  pure  air  is  drawn  into  the 
cylinder  of  the  engine  through  the  valve  shown 
at  the  bottom  of  the  combustion  chamber.  The 
piston  then  compresses  the  charge  of  air,  forcing 
a  portion  of  it 
into  the  vapor- 
izing chamber 
and  as  soon  as 
the  explosive 
charge  has 
reached  the 
proper  degree 
of  temperature 
spontaneous  or 
self-igni  tion 
takes  place. 

Oil  Vapori- 
zation, Meth- 
ods of.  Oil  en- 
gines have  two 
methods  of  va- 
porization, one 
in  which  the  oil 
is  injected  directly  into  the  cylinder  and  the 
other  where  it  is  drawn  in  with  the  air.  The 
mixture  of  oil  vapor  and  air  being  carried  on  by 
compression  in  the  cylinder,  ignition  is  caused  by 
an  electric  or  tube  igniter.  The  heat  from  the 
exhaust  is  sometimes  utilized  to  raise  the  temper- 


FIG.  25 

Cycle  of  oil  engine,  showing  the  various 
operations  during  the  cycle. 


92        GAS  AND   OIL  ENGINE  HAND-BOOK 

ature  of  the  chamber  through  which  the  oil 
passes  to  the  cylinder,  which,  with  the  heat 
caused  by  compression,  is  sufficient  to  cause 
vaporization  and  a  proper  mixing  with  the  air  to 
form  an  explosive  mixture,  the  chamber,  which 
is  heated  by  the  exhaust  in  operation,  being  first 
heated  by  a  burner. 

The  different  types  of  vaporizers  may  be 
classed  as  follows: 

A  vaporizer  into  which  the  charge  of  oil  is 
injected  by  a  spraying  nozzle  connected  to  the 
combustion  chamber  through  a  valve. 

A  vaporizer  into  which  the  oil  is  injected, 
together  with  a  small  volume  of  air,  the  greater 
volume  of  air  entering  the  cylinder  through  a 
separate  valve. 

A  vaporizer  into  which  the  oil  and  all  the  air 
supply  is  drawn,  but  without  a  spraying  device. 

A  form  of  vaporizer  into  which  the  oil  is 
injected  directly,  air  first  being  drawn  into  the 
cylinder  by  means  of  a  separate  valve,  the  explo- 
sive mixture  being  formed  only  with  the  com- 
pression. 

Oil  Vaporizer,  Crude.  On  the  Pacific  coast 
crude  oil  is  now  largely  used  for  fuel.  In  many 
instances  the  crude  oil  is  vaporized  in  a  separate 
apparatus  and  is  then  used  in  an  ordinary  gas 
engine.  This  apparatus  is  usually  separate  from 
the  engine,  the  oil  being  entirely  vaporized  before 
it  reaches  the  engine.  Such  vaporizing  apparatus 


GAS  AND  OIL  ENGINE   HAND-BOOK      93 

are  made  by  various  manufacturers,  but  in  gen- 
eral principle  they  are  similar.  The  heat  of  the 
exhaust  gases  from  the  engine  is  utilized  to  heat 
the  vaporizer  into  which  the  crude  oil  is  intro- 
duced, where  it  is  converted  into  gas. 

The  fuel  to  be  vaporized  enters  a  ribbed 
chamber  through  suitable  openings,  and  the  gas 
is  drawn  from  the  chamber  through  a  separate 
connection  to  the  engine  cylinder.  The  exhaust 
gases  from  the  engine  are  connected  to  an  outer 
chamber  and  pass  around,  heating  the  inner 
chamber  to  a  temperature  necessary  for  vaporiza- 
tion. Provision  is  made  to  draw  off  the  residue 
of  the  crude  oil,  which  is  not  capable  of  vapor- 
ization, and  provision  is  also  made  to  cleanse  the 
vaporizing  chamber  of  deposits  of  carbon  and 
other  non-combustible  matter. 

Oil  Vaporizers.  The  usual  form  of  oil  vapor- 
izers consists  of  a  heated  chamber  in  which  the 
charge  of  oil  is  transformed  into  vapor  before 
being  mixed  with  the  air  in  the  cylinder  of  the 
engine. 

Vaporizers  vary  considerably  in  their  construc- 
tion and  operation. 

In  some  the  oil  strikes  the  air  as  it  enters,  in 
others  a  pump  forces  a  jet  of  oil  against  the  sides 
of  the  vaporizing  chamber  and  is  in  this  manner 
broken  up  into  spray  and  mixed  with  the  hot  air, 
which  rapidly  vaporizes  it. 

A    form    of    oil    vaporizer    is    illustrated    in 


94        GAS  AND   OIL  ENGINE   HAND-BOOK 

Figure  26,  in  which  the  charge  of  oil  is  sprayed 
directly  into  the  vaporizing  chamber  by  means  of 


FIG.  26 

Vaporizing  chamber  of  oil  engine,  showing  the  flanges  or  ribs  in 
the  chamber  and  oil  feed  to  the  vaporizing  chamber. 

a  pump,  the  oil  passing  to  the  chamber  through 
the  small  pipe  shown  in  the  left-hand  view  in  the 
drawing. 

Overheating,  Causes  of.  The  effect  of  over- 
heating is  to  burn  up  the  lubricating  oil  in  the 
cylinder.  This  causes  a  smell  of  burning  and  an 
odor  of  hot  metal.  There  is  sometimes  a  slight 
smoke  and  the  engine  will  make  a  knocking 
sound. 

A  simple  test  in  the  case  of  an  overheated 
engine  is  to  let  a  few  drops  of  water  fall  on  the 
head  of  the  cylinder.  If  it  sizzles  for  a  few 
moments  the  overheating  is  not  bad,  but  if  the 
water  at  once  turns  into  steam,  the  case  is 
serious. 

As  soon  as  any  of  the  above  symptoms  are 
noticed : 


GAS  AND   OIL   ENGINE   HAND-BOOK       95 

The  engine  should  be  stopped  at  once. 

Kerosene  should  be  copiously  injected  into  the 
cylinder  and  the  engine  turned  by  hand  to  free 
the  piston-rings. 

Insufficient  lubrication  increases  the  friction 
between  the  piston  and  cylinder,  and  so  generates 
extra  heat.  Bad  or  unsuitable  lubricating  oil  may 
have  the  same  effect. 

Too  rich  a  mixture  also  causes  increased 
heat. 

Pistons.  The  piston  used  in  a  gasoline  engine 
cylinder  is  usually  of  the  single-acting  or  trunk 
type.  It  is  made  of  an  iron  casting  which  is  a 
good  working  fit  in  the  cylinder.  Around  the 
upper  end  of  the  piston  three  or  four  grooves  are 
cut,  and  in  these  grooves  the  piston -rings  fit. 
The  rings  are  made  of  cast  iron,  and  the  bore  of 
the  ring  being  eccentric  to  its  outer  diameter, 
there  is  a  certain  amount  of  spring  in  them,  and 
so  pressure  is  caused  against  the  cylinder  wall, 
preventing  any  of  the  expanding  gases  passing 
the  piston. 

The  lubrication  of  the  piston-rings  is  very 
important,  for  on  that  depends  the  proper  work- 
ing of  the  piston  in  the  cylinder.  In  single- 
cylinder  engines,  the  piston-rings  require  frequent 
attention,  and  kerosene  should  be  injected  into 
a  suitable  opening  at  frequent  intervals.  Occa- 
sionally the  piston  should  be  taken  out,  and  the 
rings  cleaned  with  a  brush  and  kerosene. 


96        GAS  AND   OIL  ENGINE   HAND-BOOK 

Piston  Displacement.  The  piston  displace- 
ment of  an  engine  is  the  volume  swept  out  by 
the  piston,  and  is  equal  to  the  area  of  the  cylin- 
der multiplied  by  the  stroke  of  the  piston.  The 
expression,  cylinder  volume,  is  sometimes  con- 
founded with  the  term  piston  displacement. 
This  is  erroneous,  as  the  cylinder  volume  is 
equal  to  the  piston  displacement,  plus  the  com- 
bustion space  in  the  cylinder  head. 

Pistons,  Length  of.  For  vertical  cylinder  gas 
or  oil  engines  the  length  of  the  piston  should  not 
on  any  account  be  less  than  one  and  one-quarter 
its  diameter,  while  a  length  equal  to  one  and 
one-third  or  even  one  and  one-half  diameters  is 
better.  For  engines  with  horizontal  cylinders  the 
length  of  the  piston,  in  any  case,  should  not  be 


FIG.  27 

Longitudinal  section  and  end  elevation  of  piston  for  gas  or  oil 
engine. 

less  than  one  and  one-half  diameters,  and  if  pos- 
sible one  and  two-thirds  diameters  or  over. 

A  typical  piston  for  gas  or  oil  engine  use  is 
shown  in  Figure  27. 


GAS  AND   OIL  ENGINE  HAND-BOOK       97 

Piston-rings.  To  ensure  proper  compression, 
it  is  absolutely  essential  that  the  piston-rings 
should  be  kept  lubricated,  consequently  if  the 
engine  has  been  standing  for  some  time,  the 
compression  at  the  start  is  often  poor.  Any  fail- 
ure in  the  lubrication  while  running  will,  of 
course,  have  the  same  effect,  such,  for  example, 
as  in  the  case  of  overheating,  or  when  the  supply 
is  intermittent.  Sometimes  the  piston-rings  get 
stuck  in  their  grooves  with  burnt  oil,  through 
overheating,  and  the  compression  escapes  past 
them.  Thorough  cleaning  with  kerosene  and 
fresh  lubricating  oil  will  settle  the  matter.  In 
engines  where  the  rings  are  not  pinned  in  posi- 
tion, the  slots  may  sometimes  work  round  so  as 
to  coincide. 

A  new  method  of  making  piston-rings  has 
recently  been  introduced,  for  which  several 
important  advantages  are  claimed.  The  rings 
are  turned  and  finished  to  the  correct  size  of  the 
cylinder  in  the  usual  way,  and  are  afterwards 
automatically  hammered  on  their  inside  surfaces, 
to  give  them  the  necessary  elasticity. 

The  hammering  is  made  heaviest  and  by  this 
method  a  stress  is  set  up  diametrically  opposite 
to  the  ring  joint,  and  the  hammering  gradually 
reduced  in  both  directions  till  the  joint  is  reached. 

Piston-rings,  Method  of  Turning.     A  pat 
tern  should  be  made  from  which  to  cast  a  blank 
cylinder  or  sleeve  with  two  projecting  slotted  lugs 


98        GAS  AND  OIL  ENGINE  HAND-BOOK 

on  one  end  to  bolt  same  to  face  plate  of  latlie. 
This  blank  should  first  be  turned  off  outside  to 
the  required  diameter,  making  it,  of  course, 
sufficiently  larger  to  allow  for  the  cut  in  the  rings, 
after  cutting  from  the  blank.  The  blank  should 
then  be  set  oyer  eccentric  sufficiently  to  allow  the 
thick  side  of  the  rings  to  be  twice  the  thickness 
of  the  thin  side  after  turning.  The  inside  of  the 
blank  can  then  be  bored  out,  and  the  rings  cut 
off  to  the  exact  thickness  required  with  a  good 
sharp  cutting  off  tool.  A  mandril  or  arbor 
should  be  made  with  two  cast  iron  washers  or 
collars  to  fit  on  it,  one  fastened  to  the  mandril 
and  the  other  loose,  with  lock  nut  on  mandril 
with  which  to  tighten  up  the  loose  collar.  After 
the  rings  have  been  sawed  open  and  a  piece  cut 
out  the  required  length,  they  can  be  placed  in  a 
collar  or  ring  about  1-32  to  3-64  of  an  inch 
larger  than  the  cylinder  bore,  and  slipped  on  to 
the  mandril  one  at  a  time  of  course,  with  the 
loose  collar  and  nut  off  the  same.  The  loose 
collar  and  nut  can  then  be  put  on  the  mandril, 
the  ring  clamped  tightly  between  the  two  collars, 
the  mandril  put  in  the  lathe  and  the  ring  turned 
off,  without  leaving  any  fins  or  having  to  cut  the 
ring  off  afterward  as  is  done  in  many  cases. 
This  is  the  only  way  in  which  a  perfectly  true 
ring  can  be  made. 

Figure  28  shows  two  forms  of  piston-rings,  the 
cut  or  slot  in  one  being  of  the  type  known  as  the 


GAS  AND  OIL   ENGINE  HAND-BOOK       99 


ship-lap  and  the  other  as  the  miter-cut.  Both 
forms  are  in  use,  the  ship-lap  form,  however,  is 
the  more  expensive  to  make. 

Piston  Velocity.  The  rate  of  travel  or  speed 
of  the  piston  of  a  gas  or  oil  engine  is  from  600  to 
750  feet  per  minute. 

To   ascertain   the   piston   velocity  in   feet   per 


1 


\ 


FIG.  28 

Side  and  end  elevation  of  piston-rhiers,  showing  ship-lap  and 
miter-cut  types. 


minute,  multiply  the  stroke  of  the  piston  in 
inches  by  the  number  of  revolutions  per  minute 
and  divide  the  result  by  6. 

Example:  Required  the  piston  velocity  of  an 
engine  with  9 -inch  stroke,  at  400  revolutions  per 
minute. 

Answer:    Nine  multiplied  by  400  equals  3,600, 


100      GAS  AND  OIL  ENGINE  HAND-BOOK 


GAS  AND   OIL  ENGINE   HAND-BOOK     101 

this  divided  by  6  gives  600  feet  per  minute  as  the 
piston  velocity. 

Portable  Oil  Engines.  Portable  gasoline  and 
kerosene  engines  are  used  for  a  variety  of  pur- 
poses. Such  engines  in  connection  with  circular 
saws,  electric  light  or  pumping  outfits  are  found 
very  useful.  Portable  engines  are  also  used  for 
agricultural  work,  such  as  operating  threshing 
machines,  feed  cutters  and  other  farm  machinery. 
Figure  29  shows  a  portable  oil  engine  mounted 
upon  a  truck  with  wooden  frame  and  steel  wheels 
and  running  gear.  The  engine,  cooling  appara- 
tus and  battery  are  clearly  shown  in  the  draw- 
ing. 

As  portable  engines  require  to  be  frequently 
moved  from  place  to  place,  the  design  of  the 
outfit  should  be  as  light  as  possible  and  yet  sub- 
stantial in  construction,  so  that  it  may  be  moved 
from  one  place  to  another  in  the  shortest  possible 
time  and  with  the  least  expense  for  transporta- 
tion. 

As  portable  engines  are  often  in  places  where 
a  supply  of  water  is  not  available,  the  water- 
cooling  apparatus  forms  an  important  part  of  the 
outfit. 

Another  foim  of  portable  engine  is  shown  in 
Figure  30,  which  is  simply  mounted  on  skids 
and  may  be  moved  from  place  to  place  by  two 
persons.  Such  an  outfit  is  of  much  smaller  capac- 
ity than  the  one  previously ^cjese^ipeti \and ;  il 


102      GAS  AND   OIL   ENGINE   HAND-BOOK 


O 
CO 


GAS  AND   OIL   ENGINE  HAND-BOOK       103 

trated,  but  is  found  useful  for  many  purposes 
where  small  power  is  needed. 

Premature  Ignition,  Causes  of.  Too  great 
a  degree  of  compression  of  the  charge,  an  incan- 
descent deposit  of  soot  or  foreign  substance  in 
the  combustion  chamber,  from  slow  or  incom- 
plete combustion  of  the  previous  charge,  which 
remains  sufficiently  heated  to  fire  the  new  charge 
before  the  completion  of  the  compression  stroke, 
burning  gases  drawn  from  the  exhaust-pipe  into 
the  combustion  chamber,  from  the  overheating 
of  the  exhaust  valve.  Premature  ignitions  are 
also  attributed  to  the  use  of  low-flash  test  oils  for 
lubricating  the  cylinder,  and  too  little  air  in  the 
charge  will  also  cause  too  rapid  firing,  or  in  the 
case  of  the  primary  form  of  electric  ignition  from 
overheated  igniter  points. 

Primary-spark  Coil.  This  form  of  induction 
coil  is  generally  used  for  ignition  purposes  on  gas 
and  gasoline  engines  fitted  with  a  mechanical 
make-and-break  form  of  spark,  which  is  located 
within  the  combustion  chamber  of  the  engine 
itself. 

It  consists  of  two  principal  parts,  a  core,  made 
of  a  bundle  of  soft  iron  wire,  and  a  coil  of  wire 
around  this  core  composed  of  from  3  to  5  layers 
of  turns  of  insulated  copper  wire,  varying  in 
diameter  from  No.  16  to  No.  12,  B.  &  S.  Gauge, 
according  to  the  battery  conditions  under  which 
the  coil  has  to  operate.  The  iron  core  may  vary 


104     GAS  AND   OIL  ENGINE  HAND-BOOK 


from  three-eighths  of  an  inch  in  diameter  and 
6  inches  long,  to  three-fourths  of  an  inch  in 
diameter,  and  12  to  15  inches  long,  depending 
upon  the  intensity  and  capacity  of  the  spark 
required. 

Primary-spark  Plug.  The  construction  of 
one  of  the  usual  forms  of  make-and-break  pri- 
mary-spark plugs  is  clearly  shown  in  Figure  31. 
The  upper  and  fixed  electrode  is  insulated  by 


FIG.  31 

Primary-spark  plug,  showing  fixed  and  movable  electrodes  and 
platinum  contact-points. 

means  of  mica  or  lava  washers  and  is  secured  in 
place  by  means  of  a  lock  nut  and  washer.  The 
movable  electrode  has  a  coil  spring  around  its 
outer  end,  one  end  of  the  spring  secured  to  the 
spindle  of  the  electrode  and  the  other  to  the  hub 
of  a  small  trigger  on  the  extreme  end  of  the 
spindle.  This  construction  allows  for  any  wear 
on  the  contact-points  and  at  all  times  ensures  a 
good  contact  between  them. 


GAS  AND  OIL  ENGINE   HAND-BOOK     105 

Prony  Brake.  This  simple  device  gives  the 
actual  energy  in  foot-pounds  per  minute  delivered 
by  the  engine  at  its  driving  shaft. 

The  apparatus  for  making  a  brake  test  is  fully 
illustrated  in  Figure  32.  Two  brake-blocks  A 
partially  surround  the  pulley  P  and  are  attached 
to  the  clamping  pieces  B  and  C,  which  hold  the 
brake-blocks  upon  the  pulley  by  means  of  the 
bolts  D,  springs  E  and  thumb-nuts  F.  The 
lever  G  is  double-ended  for  the  dual  purpose  of 
balancing  itself  and  also  supplying  a  place  of 
attachment  for  the  weight  W  to  balance  the 
weight  of  the  spring  scale  S. 

In  using  this  form  of  Prony  brake,  the  engine 
is  started  in  the  direction  indicated  by  the  arrow 
on  the  drawing,  the  brake-blocks  A  are  then 
tightened  by  means  of  the  springs  E  and  thumb - 
nuts  F.  Then  the  reading  of  the  spring  scale  S 
and  the  speed  of  the  pulley  P  are  taken. 

The  engine  should  be  tested  at  varying  speeds 
and  the  pull  on  the  spring  scale  S  noted  for  each. 

The  actual  horsepower  can  then  be  calculated 
for  each  test  and  what  is  known  as  the  critical 
speed  of  the  engine  determined,  that  is  the  speed 
at  which  the  engine  develops  the  greatest  brake 
horsepower. 

The  following  formula  gives  the  actual  horse- 
power obtained  from  the  results  of  a  Prony  brake 
test:  Let  L  be  the  length  of  the  scale  lever  in 
inches,  and  S  the  pull  indicated  by  the  spring 


106      GAS  AND   OIL  ENGINE  HAND-BOOK 


GAS  AND  OIL   ENGINE   HAND-BOOK!      107 

scale  in  pounds.     If  N  be  the  number  of  revolu- 
tions per  minute  of  the  pulley   R  and  B.H.P  the 
actual  or  brake  horsepower  of  the  engine,  then 
LXSXN 
63,025 

Example:  A  motor  of  5  inches  bore  and 
7j  inches  stroke  at  400  revolutions  per  minute 
gives  a  pull  at  the  spring  scale  of  48  pounds,  the 
scale  lever  is  24  inches  long.  What  is  the  brake 
horsepower  of  the  motor? 

Answer:  Twenty-four  inches  multiplied  by 
48  and  by  400  equals  460,800 — this  divided  by 
63,025  gives  7.30  as  the  brake  horsepower  of  the 
motor. 

The  weight  J  is  shown  for  use  in  case  the  floor 
of  the  testing  room  should  be  of  brick  or  cement : 
if  of  wood  the  eye-bolt  H  can  be  screwed  directly 
into  the  floor. 

Repairing  a  Gas  or  Oil  Engine.  The  piston 
should  be  thoroughly  washed  with  kerosene. 
When  putting  the  piston  back  in  the  cylinder, 
each  ring  should  be  put  separately  in  exact  posi- 
tion in  its  groove  as  regards  the  dowel-pin  (if 
any)  in  the  ring  groove  before  the  ring  enters 
the  cylinder.  The  piston,  the  rings,  and  the 
inside  of  the  cylinder  should  all  be  carefully 
cleaned  and  well  lubricated  with  proper  oil  before 
the  piston  is  again  put  in  place.  Where  the  rings 
require  cleaning,  this  should  be  done  by  washing 
with  kerosene.  If  the  piston-rings  require  to  be 


108     GAS  AND  OIL  ENGINE  HAND-BOOK 

taken  off  the  piston,  they  should  be  sprung  open 
by  having  pieces  of  sheet  metal  about  one- 
sixteenth  of  an  inch  'thick  and  about  one-half 
inch  wide  inserted  between  the  ring  and  the 
body  of  piston. 

The  inlet  and  exhaust- valves  should  be  fre- 
quently taken  out,  cleaned  and  examined,  and,  if 
necessary,  reground  in.  Finely-powdered  emery 
or  tripoli  are  very  satisfactory  to  grind  the  valves 
in  with. 

Care  should  be  taken,  in  replacing  the  valves, 
that  they  are  clean  and  free  from  rust  or  carbon, 
and  are  allowed  to  drop  on  their  seats  freely  and 
do  not  stick  in  their  guides. 

The  crank-shaft  bearings  will  occasionally 
require  taking  up  as  they  show  signs  of  wear  and 
commence  to  knock  or  pound.  For  this  adjust- 
ment, liners  are  placed  between  the  cap  and  the 
lower  half  of  the  bearings.  These  liners  can  be 
occasionally  reduced  in  thickness,  so  that  the  cap 
is  allowed  to  come  down  closer  to  the  shaft. 

Secondary  Coil.  Any  form  of  electrical  igni- 
tion requires  some  outside  source  of  electric 
energy  such  as  a  generator  or  battery  to  produce 
a  spark  in  the  combustion  chamber  of  the  motor. 
A  primary  or  secondary  induction  coil  is  neces- 
sary in  connection  with  the  source  of  electric 
energy  to  give  a  spark  of  sufficient  intensity  to 
properly  ignite  the  compressed  charge  in  the 
combustion  chamber  of  the  engine.  This  method 


GAS  AND  OIL  ENGINE  HAND-BOOK     109 


of  ignition  provides  a  means  of  regulating  the 
motor  speed  by  advancing  and  retarding  the  point 
of  ignition,  or  time  of  igniting  the  explosive  charge. 
The  coil  first  mentioned  is  known  as  a  primary- 
spark  coil,  from  the  fact  that  the  spark  or  arc  is 
produced  by  the  direct  effect  of  the  battery  or 
generator  current  flowing  in  the  coil.  This  form 
of  spark  will  not  arc  or  jump  across  a  space 


FIG.  33 

econdary-spark  circuit,  showing  coil  spark  plug,  battery  and 
commutator. 


between  two  points,  but  simply  occurs  between 
the  contact-points  on  the  breaking  of  the  contact. 

The  second  form  of  induction  coil  is  generally 
known  as  a  secondary-spark  coil,  because  the  arc 
or  spark  is  produced  in  the  secondary  winding  of 
the  coil,  and  will  jump  or  arc  across  a  space 
between  two  fixed  points,  without  the  points  first 
coming  in  contact. 

Figure  33  shows  the  wiring  circuit  for  a  gas  or 


110        GAS  AND  OIL  ENGINE   HAND-BOOK 

oil  engine  equipped  with  the  secondary  or  jump- 
spark  form  of  electrical  ignition.  The  battery, 
commutator,  spark  coil  and  spark  plug  are 
plainly  indicated,  also  the  wiring  connections 
from  the  spark  coil  to  the  engine  and  between 
the  coil,  battery  and  commutator. 

Smoke  from  Cylinder,  Cause  of.  If  black 
smoke  comes  from  the  cylinder,  it  may  arise 
from  leaky  piston,  overheating,  want  of  or  excess- 
ive lubrication,  too  rich  mixture,  faulty  combus- 
tion, faulty  ignition. 

Solders  and  Spelters.  Solders  and  spelters 
for  use  with  different  metals,  and  their  propor- 
tional parts  by  weights  are 

Solder  for: 

Electrician's  use 1 — Tin,  1 — Lead. 

Gold 24— Gold,  2— Silver,   1— Copper. 

Platinum 1 — Copper,  3  Silver. 

Plumber's — Hard  .  .  .1 — Lead,  2— Tin. 
Soft 3— Lead,  1— Tin. 

Silver — Hard 1 — Copper,  4 — Silver. 

Soft 1— Brass,  2— Silver. 

Tin— Hard 2— Tin,  1— Lead. 

Soft 1 — Tin,  1— Lead. 

Spelter  for : 

Fine  brass  work 8 — Copper,  8 — Zinc,  1 — Silver. 

Common  brass 1 — Copper,  1 — Zinc. 

Cast  iron 4 — Copper,  3 — Zinc. 

Steel 3— Copper,  1— Zinc. 

Wrought  iron 2 — Copper,  1 — Zinc. 

Starting  a  Gas  Engine.  If  an  incandescent 
tube  is  used  for  the  ignition,  the  Bunsen  burner 
should  first  be  lighted.  While  the  tube  is  being 
heated,  oil  up  all  the  working  parts  of  the 
engine. 


GAS  AND  OIL  ENGINF    HAND-BOOK      111 

If  electric  ignition  is  used,  close  the  battery 
switch. 

Next,  open  the  gas  valve  so  as  to  admit  a 
charge  of  gas  into  the  inlet-valve  chamber,  along 
with  the  air,  then  give  the  flywheels  four  or  five 
quick  turns  until  the  engine  starts. 

Open  the  lubricator  on  the  cylinder  and  see 
that  it  is  adjusted  so  as  to  allow  about  10  drops 
of  oil  to  flow  per  minute. 

The  water  in  the  cooling  tank  should  always 
be  at  least  6  inches  above  the  overflow  pipe  from 
the  top  of  the  cylinder  jacket. 

If  the  engine  does  not  ignite  its  first  or  second 
charge  there  is  a  reason  for  it,  and  the  cause  of 
the  trouble  should  be  located. 

Starting  a  Gasoline  Engine.  The  instruc- 
tions given  for  starting  a  gas  engine  apply  also  to 
a  gasoline  engine,  with  the  exception  that  the 
supply  of  gasoline  from  the  carbureter  or  mixing 
valve  should  be  regulated  according  to  the  instruc- 
tions given  by  the  manufacturer  of  the  engine. 

The  fuel  supply  of  a  gasoline  engine  is  usually 
regulated  by  means  of  a  needle -valve,  which 
should  be  carefully  cleaned  at  regular  intervals. 
In  engines  using  a  pump  feed,  the  supply  of 
gasoline  is  usually  regulated  by  adjusting  the 
stroke  of  the  pump,  or  by  regulating  the  opening 
in  a  by-pass,  so  that  a  portion  of  the  fuel  is 
pumped  through  the  by-pass  and  returns  to  the 
supply  tank. 


112     GAS  AND  OIL  ENGINE  HAND-BOOK 

Starting  a  Gasoline  or  Kerosene  Engine  for 
the  First  Time.  Don't  attempt  to  start  an 
engine  the  first  time  until  the  following  points 
are  found  to  be  right: 

That  there  is  good  compression. 

That  the  batteries  are  set  up  properly  and 
wired  correctly. 

That  a  good  bright  spark  is  obtained  by 
touching  the  ends  of  the  two  wires  at  the  engine 
together. 

That  there  is  a  good  supply  of  gasoline  or  oil 
in  the  supply  tank. 

That  the  gasoline  or  oil  pump  works  freely 
and  that  the  gasoline  or  oil  reaches  the  vaporizer. 

That  the  inlet  and  exhaust- valves  are  not 
stuck,  and  that  they  work  freely  and  seat 
quickly. 

Starting  a  Gas  or  Oil  Engine,  General  Direc- 
tions for.  The  successful  starting  or  running  of 
an  engine  depends  entirely  on  the  mixture  of  gas 
and  air,  and  proper  ignition. 

As  all  of  these  are  under  full  control  of  the 
operator  at  all  times,  it  lies  entirely  with  him  as 
to  whether  the  engine  starts  and  runs  properly  or 
not. 

The  engine  cannot  start  itself,  it  must  be 
started. 

If  the  above  conditions  and  the  following 
instructions  are  properly  carried  out,  the  engine 
will  start  without  fail. 


GAS  AND  OIL  ENGINE  HAND-BOOK      113 

Before  starting  up  the  engine,  go  over  all  the 
connections  carefully  and  see  that  everything  is 
in  place  according  to  the  instructions. 

See  that  the  gasoline  tank  is  full. 

Pump  up  the  gasoline  by  working  the  pump 
lever  until  the  feed  chamber  is  full. 

Close  the  cock  in  the  bottom  of  the  water  tank 
and  fill  the  tank  to  near  the  top  pipe,  but  not  full 
enough  to  run  into  the  pipe  if  the  weather  is 
freezing. 

Never  let  the  water  enter  the  cylinder  or  valve 
chamber  jackets  in  cold  weather  until  the  engine 
has  run  long  enough  to  become  warm. 

Open  the  burner- valve,  first  passing  a  nail  or 
match  down  through  a  hole  in  the  burner  tube, 
and  hold  it  so  as  to  turn  the  stream  of  gasoline 
down  and  fill  the  burner  pan,  then  close  the  valve 
and  light  the  gasoline. 

When  the  gasoline  in  the  pan  is  burned  out, 
open  the  valve  and  light  the  vapor,  which  should 
burn  with  a  strong,  steady  blue  flame. 

The  globe- valve,  next  to  the  burner,  is  to  help 
regulate  the  flame,  and  should  be  closed  nearly 
tight. 

While  the  burner  is  heating  the  tube,  which 
should  take  from  two  to  three  minutes,  if  it  is 
properly  regulated,  see  that  the  grease  cups  are 
full. 

Oil  up  all  parts  of  the  engine.  Fill  the  lubri- 
cator and  start  it  to  feed. 


114     GAS  AND  OIL  ENGINE  HAND-BOOK 

Turn  the  engine  round  by  hand  several  times 
to  see  that  everything  is  in  its  proper  place,  and 
nothing  binding. 

Examine  the  flywheel  keys  and  see  that  they 
are  driven  tight. 

When  the  tube  is  hot  the  engine  is  ready  to 
start. 

If  electric  ignition  is  used,  close  the  battery 
switch.  Almost  close  the  air-valve  before  start- 
ing the  engine. 

The  object  of  closing  the  air-valve  is  to  obtain 
a  rich  charge  and  make  it  surer  to  explode. 

The  amount  of  fuel  can  be  regulated  at  will. 

It  can  be  made  so  weak  that  it  will  not 
explode  or  so  strong  it  cannot  be  ignited. 

When  black  smoke  issues  from  the  exhaust 
pipe,  the  mixture  is  too  strong. 

Starting  a  Kerosene  Engine.  The  methods 
usually  employed  to  ignite  the  explosive  charge 
in  the  combustion  chamber  of  an  oil  engine  are: 
By  means  of  an  electric  spark,  an  incandescent 
tube,  or  a  vaporizing  chamber  with  projecting 
ribs  which  are  kept  incandescent  by  the  heat  of 
the  previous  charge. 

The  proper  heating  of  the  vaporizing  chamber 
is  the  first  and  most  important  thing  to  be 
attended  to  when  starting  an  oil  engine  and  care 
should  be  taken  that  the  vaporizer  is  sufficiently 
hot  before  attempting  to  start  the  engine. 

The  Bunsen  burner  or  lamp  should  be  kept 


GAS  AND  OIL  ENGINE  HAND-BOOK       115 

burning  for  five  or  ten  minutes  or  even  longer, 
according  to  the  size  of  the  engine.  When  the 
vaporizer  is  sufficiently  heated,  turn  on  the  fuel 
oil  supply  and  give  the  flywheels  four  or  five 
quick  turns,  if  all  other  conditions  are  right  the 
engine  should  at  once  start.  See  that  the  cylin- 
der lubricator  and  the  oil  cups  on  the  crank  shaft 
bearings  are  filled  before  starting  the  engine,  also 
oil  the  wrist-pin  end  of  the  connecting-rod  and 
the  cam  shaft  bearings.  After  the  engine  is 
started,  open  the  valve  in  the  air-inlet  pipe  until 
the  engine  attains  its  normal  speed. 

When  electric  ignition  is  used,  the  battery 
switch  should  always  be  closed  before  an  attempt 
is  made  to  start  the  engine. 

With  the  hot  tube  form  of  ignition,  the  tube 
should  always  be  incandescent  before  starting  the 
engine. 

Always  be  sure  that  the  supply  of  water  to  the 
cylinder  jacket  is  ample. 

With  oil  engines  which  operate  on  the  vapor- 
izer principle,  it  is  found  absolutely  necessary  to 
heat  the  fuel  before  it  enters  the  cylinder.  In 
some  oil  engines  it  is  not  necessary  to  heat  the 
fuel  before  it  enters  the  cylinder,  as  it  is  injected 
against  a  highly  heated  surface. 

Starting  Oil  Engines,  New  Method  of.  A 
method  of  starting  an  oil  engine  has  of  recent  years 
been  used  in  which  alcohol,  gasoline,  or  naphtha  is 
burnt  for  a  few  minutes  instead  of  kerosene. 


116     GAS  AND  .OIL  ENGINE  HAND-BOOK 

This  method  is  advantageous  in  that  the  engine 
when  cold  can  be  started  without  the  use  of  an 
external  heater.  The  lighter  fuel  is  supplied  to 
the  vaporizer  or  cylinder  until  the  vaporizing 
attachment  has  become  heated  by  the  internal 
combustion  to  the  temperature  necessary  for 
vaporizing  the  heavier  fuel,  then  the  fuel  supply 
is  changed,  the  supply  of  lighter  fuel  being 
stopped.  Where  a  vaporizer  is  used  in  which 
the  charge  is  not  explosive  until  after  compres- 
sion, an  independent  electric  igniter  is  used  to 
ignite  the  charge,  and  is  only  in  operation  until 
the  vaporizer  becomes  properly  heated. 

Starting  Troubles.  If,  after  turning  the 
flywheels  of  the  engine  four  or  five  times,  it 
refuses  to  start,  the  trouble  may  be  due  to  any 
one  of  the  following  causes:  Loss  of  com- 
pression, faulty  ignition,  improper  mixture, 
water  in  the  cylinder,  or  oil  on  the  igniter  con- 
tact-points. 

Sometimes  an  engine  will  start  readily,  but 
dense  smoke  having  a  strong  odor  will  issue  from 
the  exhaust-pipe.  This  may  be  an  indication 
that  the  mixture  is  too  rich,  although  it  is  fre- 
quently due  to  an  excess  of  lubricating  oil  in  the 
cylinder.  To  correct  the  mixture,  more  air 
should  be  admitted  to  the  cylinder. 

Failure  of  an  engine  to  start  is  more  often 
occasioned  by  too  weak  than  by  too  rich  a  mix- 
ture. The  first  thing  to  do,  if  regulating  the  air 


GAS  AND  OIL  ENGINE   HAND-BOOK     117 

does  not  correct  it,  is  to  ascertain  if  the  fuel 
supply  pipe  is  free  from  obstructions.  This  pipe 
is  generally  not  very  large,  and  is  more  or  less 
crooked.  A  partial  stoppage  of  the  pipe  will 
therefore  result  in  a  too  weak  mixture. 

Stopping  a  Gas  or  Oil  Engine.  The  first 
things  to  do  when  stopping  an  engine  are: 

Shut  off  the  gas  or  oil  supply. 

Close  all  oil  cups  or  lubricators. 

Switch  off  the  battery  or  turn  out  the  ignition 
tube  burner. 

Wipe  off  the  engine  and  see  that  it  is  in  good 
shape  for  the  next  run. 

While  cleaning  the  engine  examine  all  nuts 
and  bolts,  all  points  needing  adjustment.  Exam- 
ine the  condition  of  the  crank  shaft  and  other 
bearings.  If  they  are  hot  or  show  signs  of  heat- 
ing, locate  the  cause  if  possible  and  remove  it 
before  again  starting  the  engine. 

Do  not  fail  to  throw  the  battery  switch  off 
when  the  engine  is  not  running,  as  there  is 
always  a  possibility  of  short  circuiting  the  battery 
and  possibly  ruining  it  in  a  few  hours. 

It  will  pay  to  always  keep  the  engine  neat  and 
clean.  Examine  the  engine  occasionally  and  see 
that  everything  is  working  properly. 

If  the  engine  has  not  to  be  re-started  for  some 
days,  it  is  a  good  plan  to  turn  off  the  oil  supply 
to  the  cylinder  for  a  short  period  before  stopping, 
as  what  oil  remains  will  be  burnt  out,  and  there 


118     GAS  AND  OIL  ENGINE   HAND-BOOK 

is  less  liability  to  the  gumming  of  the  piston  and 
cylinder  or  valves. 

Stopping  Troubles.  Some  of  the  principal 
causes  of  stopping  of  gas  or  oil  engines  are  as 
follows : 

Bad  design  or  construction  of  the  engine, 
improper  mixture  of  fuel  and  air,  defective  water 
circulation  or  insufficient  cooling  of  the  cylinder, 
leakage  of  the  piston,  leakage  of  the  valves  or 
valve  joints,  improper  or  insufficient  lubrication, 
governor  gear  defective,  back  pressure  from  foul- 
ing of  the  exhaust  with  residue,  ignition  mech- 
anism worn  or  defective,  imperfect  compression 
or  combustion,  leak  in  the  inlet-pipe,  premature 
ignition,  misfiring,  backfiring,  or  the  ignition 
wrongly  timed. 

Tachometer.  A  tachometer  is  an  instrument 
for  indicating  the  number  of  revolutions  made  by 
a  machine  in  a  unit  of  time — usually  one  minute. 

Tanks,  Capacity  of  Cylindrical.  To  ascertain 
the  capacity  in  gallons  of  a  cylindrical  tank  of 
given  length,  multiply  the  area  of  the  cross-sec- 
tion of  the  tank  in  square  inches  by  the  length  of 
the  tank  in  inches,  and  divide  the  product  by 
231,  the  result  will  be  the  capacity  of  the  tank 
in  gallons. 

Tanks,  Installation  of  Gasoline.  The  proper 
method  of  installing  the  supply  tank  for  a  gaso- 
line engine  is  shown  in  Figure  34. 

The  vault  for  the  reception  of  the  supply  tank 


GAS  AND  OIL  ENGINE  HAND-BOOK      119 


should  be  walled  with  brick  of  good  quality  and 
well  cemented  so  as  to  exclude  water,  the  cover 
of  the  vault  should  also  be  water-tight.  Shut-off 


FIG.  34 

Gasoline  tank  installation,  showing  location  of  tank,  shut-off 
cocks  and  method  of  piping. 

valves  or  cocks  should  be  placed  in  both  the 
supply  and  overflow  pipes  as  shown.  The  sup- 
ply tank  should  be  made  of  heavy  galvanized  iron 
or  steel  a  ad  well  riveted. 

A  screen  of  fine  wire  gauze  should  always  be 
fitted  in  the  mouth  of  the  filling  opening  of  the 
supply  tank,  to  prevent  the  entrance  of  dirt  or 
other  foreign  substances  which  may  be  in  the 
gasoline. 

A  small  vent  opening  should  be  made  in  the 
cap  or  cover  of  the  filling  opening  to  allow  of  the 


120      GAS  AND  OIL  ENGINE  HAND-BOOK 


ingress  of  air,  otherwise  the  gasoline  pump  will 
not  work  properly. 

Throttle,  Use  of.  For  the  purpose  of  regu- 
lating or  controlling  the  speed  of  gas  or  oil 
engines,  throttling  devices  are  sometimes  used  to 
choke  or  partially  cut  off  the  supply  of  explosive 
mixture,  being  drawn  in  the  cylinder  of  the 
engine. 

A  butterfly-valve  or  form  of  throttle  commonly 
used  for  this 


is 


purpose 
shown  in  Fig- 
ure 35.  It 
has  a  valve- 
chamber  A, 
valve  B  and 
lever  C.  The 
valve  is  loca- 
ted at  any  suit- 
able point  in 
the  inlet-pipe 
of  the  engine, 
between  the  mixing-valve  or  vaporizer  and  the 
inlet- valve  chamber. 

Two-cycle  Engine,  Construction  of.  Fig- 
ure 36  shows  a  vertical  cross-section  of  a  two- 
cycle  type  of  marine  engine.  C  is  the  crank 
chamber.  It  has  two  feet,  or  lugs,  D  as  shown 
in  the  drawing,  for  the  purpose  of  attaching  it  to 
its  position  in  a  boat  or  elsewhere.  There  is  an 


FIG.  35 

Throttle  for  regulating  the  volume  of  explo- 
sive charge  to  the  engine  cylinder. 


GAS  AND  OIL  ENGINE   HAND-BOOK     121 


M 


W 


opening  at  A  for  the  reception  of  the  mixing- 
valve.  The  flywheel  F,  crank  shaft  G,  connecting- 
rod  H,  piston  P,  inlet -port  B,  baffle-plate  J  and 
exhaust-opening  E,  are  plainly  shown  in  the 
drawing. 

To  the  top  of  the  piston  P  is  attached  a  cone- 
pointed  projection  K.  This  is  on  the  right-hand 
side  and  is  placed 
there  to  break 
the  electrical  cir- 
cuit between  the 
contact-points  of 
the  igniter.  This 
is  effected  by  the 
cone  -  point  K 
striking  the  right- 
hand  end  of  the 
lever  L,  which 
causes  the  lever 
to  rise  at  that  end 
and  fall  at  the 
oi  h"e  r,  thus 
breaking  the  con- 
tact between  it 
and  the  insulated 
igniter  terminal 
M.  This  break- 
age of  the  circuit  causes  a  spark  to  occur  between 
the  left-hand  end  of  the  lever  L  and  the  point  with 
which  it  was,  a  moment  before,  in  contact.  This 


FIG.  36 

Vertical  cross-section,  showing  the  con- 
struction of  a  two-cycle  gas  or 
gasoline  engine. 


122     GAS  AND  OIL  ENGINE  HAND-BOOK 


action  takes  place  once  in  each  revolution  of  the 
motor  and  just  before  the  piston  reaches  the  end 
of  its  upward  stroke. 

The  ignition  may  be  retarded  or  advanced  by 
raising  or  lowering  the  fulcrum  of  the  lever  L, 
by  means  of  the  eccentric  shown. 

The  upper  part  of  the  cylinder  is  incased  by  a 
water  jacket  W,  as  is  the  cylinder  head  or 
cover  N. 

Two-cycle  Engine,  Principle  of.  Figure  37 
gives  two  diagrammatic  views  of  the  operation  of 


FIG.  37 

Two-cycle  motor  diagrams,  showing  the  various  operations 
during  the  cycles. 

a  two-cycle  gas  or  oil  engine.  It  shows  an  inlet- 
valve  A,  port  or  passage  B,  crank  case  C, 
exhaust  opening  E  and  piston  P.  When  the 
piston  has  reached  the  position  shown  in  Dia- 
gram No.  1,  it  has  forced  a  charge  of  explosive 


GAS  AND  OIL  ENGINE  HAND-BOOK      123 

mixture  from  the  crank  case  through  the  port  or 
passage  into  the  cylinder.  The  piston  then 
moves  to  the  position  shown  in  Diagram  No.  2, 
and  while  doing  so,  closes  the  port  or  passage 
and  the  exhaust  opening,  the  compressed  charge 
is  then  ignited,  an  explosion  occurs  and  the 
piston  is  forced  out  to  the  position  shown  in  Dia- 
gram No.  1.. 

The  admission  of  the  new  charge  of  explosive 
mixture  to  the  crank  case  is  controlled  by  the 
action  of  the  piston.  As  the  latter  travels  away 
from  the  crank  case,  it  has  a  tendency  to  create 
a  partial  vacuum  in  the  latter.  This  operation 
draws  the  inlet-valve  inward  and  admits  the  new 
charge. 

The  baffle-plate  shown  on  the  head  of  the 
piston  directs  the  new  charge  from  the  crank  case 
towards  the  combustion  chamber  end  of  the 
cylinder,  providing  as  nearly  as  possible  a  pure 
charge  of  mixture  and  assisting  in  the  expulsion 
of  the  burned  gases  left  in  the  cylinder  from  the 
last  explosion. 

As  this  type  of  engine  draws  in  a  charge  of  ex- 
plosive mixture,  compresses  it,  ignites  it  and  dis- 
charges the  products  of  combustion  while  the 
piston  makes  one  complete  travel  backward  and 
forward,  it  consequently  has  a  working  stroke  or 
power  impulse  every  revolution  of  the  crank-shaft. 

Two -cycle  Marine  Engine.  A  single  cylinder 
two-cycle  type  of  marine  engine  mounted  on  a 


124     GAS  AND  OIL  ENGINE  HAND-BOOK 

base  with  reversing  gear,  propeller  and  shaft  is 
shown  in  Figure  38.  Such  outfits  are  made  in 
single  units  of  from  1?  to  ?i  horsepower. 

Valves.  A  valve  in  a  very  bad  or  pitted  con- 
dition causes  bad  compression  and  the  exhaust- 
valve  should  be  ground  occasionally.  After 


FIG.  38 

Two-cycle  marine  engine,  with  reversing  mechanism,  propeller 
shaft  and  propeller  mounted  on  base  plate. 

grinding  a  valve  be  sure  that  there  is  ample 
clearance  between  the  valve  and  the  lifter.  It 
should  have  not  less  than  one-thirty-second  of  an 
inch,  otherwise  when  the  valve  becomes  hot  it 
will  not  seat  properly,  poor  compression  being 
the  result.  In  grinding  a  valve  there  is  no  occa- 
sion to  use  force,  and  the  grinding  should  be 
done  lightly,  the  valve  being  lifted  from  time  to 
time  so  that  any  foreign  substance  in  the  emery 


GAS  AND  OIL  ENGINE  HAND-BOOK      125 

will  not  cut  a  ridge  in  the  seat  or  the  valve  itself. 
After  grinding  a  valve  always  wash  out  the  valve 
seat  with  a  little  kerosene  and  be  careful  that 
none  of  the  einery  is  allowed  to  get  into  the 
engine  cylinder. 

Sometimes  an  engine  may  suddenly  stop  from 
the  failure  of  a  valve  to  seat  properly.  This  may 
be  due  to  the  warping  of  the  valve  through  the 
engine  having  run  dry  and  become  hot,  or  it  may 
be  from  the  failure  of  the  valve  spring  or  the 
sticking  of  the  valve-stem  in  its  guides.  The 
valve  should  be  removed,  and  the  stem  cleaned 
and  scraped,  or  straightened  if  it  requires  it, 
until  it  moves  freely  in  the  guide,  and  the  spring 
is  given  its  full  tension.  If  the  valve  still  leaks 
so  that  the  engine  will  not  start  or  develop  suffi- 
cient power,  the  valve  will  have  to  be  ground 
into  its  seat. 

Valves  which  need  re-seating  should  first  be 
ground  in  place  with  fine  emery  and  oil,  then 
finished  with  tripoli  and  water. 

Valves  and  Valve-chambers.  The  dimen- 
sions of  the  inlet  and  exhaust- valve  openings  are 
governed  by  the  diameter  of  the  cylinder  and  the 
piston  velocity  in  feet  per  minute.  The  form  of 
valve-chamber  in  general  use  is  made  separate 
and  bolted  to  the  cylinder.  The  valve-chamber 
can  then  be  entirely  renewed  if  necessary  and  at 
small  expense.  Other  forms  of  valve-chambers 
have  the  valves  placed  horizontally  in  the  cyl- 


126     GAS  AND   OIL  ENGINE  HAND-BOOK 

inder  head.  In  any  case  the  valves  should  be 
brought  as  close  as  possible  to  the  inside  of  the 
cylinder,  the  clearance  space  in  the  ports  being 
reduced  to  a  minimum. 

In  engines  of  large  size  the  inlet  and  exhaust- 
valve  chamber  is  surrounded  by  a  water  jacket, 
which  maintains  its  proper  temperature  and  pre- 
vents the  valve  seats  being  warped  from  over- 
heating, which  might  otherwise  occur. 

When  the  inlet-valve  is  atmospherically  or  suc- 
tion operated,  it  is  opened  by  the  partial  vacuum 
in  the  cylinder  during  the  suction  period,  and 
closed  by  a  spring.  The  inlet  and  exhaust-valve 
openings  are  usually  made  of  such  a  diameter  that 
the  velocity  of  the  gas  as  it  enters  the  cylinder  is 
about  100  feet  per  second,  the  velocity  of  the 
exhaust  gases  through  the  exhaust  opening  being 
about  80  feet  per  second. 

Valves,  Diameter  and  Lift  of.  To  ascertain 
the  proper  diameter  of  inlet  and  exhaust-valve 
openings  and  the  lift  of  the  valve  to  give  an 
opening  equal  to  the  area  of  the  valve  opening, 
the  following  formulas  will  be  found  useful. 

Let  B  be  the  bore  of  the  motor  cylinder  in 
inches,  and  S  the  stroke  of  the  piston  also  in 
inches.  As  R  is  the  number  of  revolutions  per 
minute  and  D  the  required  diameter  of  the  valve 
opening,  then 

_BXSXR 

D~  15,006" 


GAS  AND   OIL  ENGINE  HAND-BOOK     127 

Example  :  Required  the  diameter  of  the  admis- 
sion-valve opening  for  a  motor  of  6-inch  bore 
and  9-inch  stroke  at  600  revolutions  per  minute. 

Answer:  As  6  multiplied  by  9  and  by  600 
equals  32,400,  then  32,400  divided  by  15,000 
gives  2.16  inches  as  the  diameter  of  the  valve 
opening. 

The  lift  of  the  45  -degree  bevel-seat  form  of 
valve  requires  to  be  about  three-eighths  of  the 
diameter  of  the  valve  opening:  that  is,  if  L  is  the 
required  lift  of  the  valve  and  D  the  diameter  of 
the  valve  opening,  then 


The  bevel-seat  form  of  valve  is  to  be  preferred 
to  the  flat-seat  or  mushroom  type  of  valve,  for 
two  reasons:  first,  that  it  is  more  readily  kept  in 
shape  by  re-grinding,  and  second,  it  gives  a  freer 
and  more  direct  passage  for  the  gases. 

For  an  atmospherically  operated  admission- 
valve  which  will  insure  practically  a  full  charge 
in  the  motor  cylinder  the  formula  should  be 

BXSXR 
12,750 

Both  inlet  and  exhaust-valves  should  be  of 
ample  area  and  short  lift,  and  be  arranged  so 
that  they  may  be  readily  inspected  and  adjusted, 
and  with  as  few  joints  as  possible. 


128     GAS  AND   OIL  ENGINE  HAND-BOOK 


Valve  Lifters.  Figure  39  illustrates  a  form  of 
valve  operating  mechanism  in  which  the  valve 

is  actuated  by 
means  of  a  roller 
upon  the  end  of 
a  rocker  arm,  to 
the  upper  side  of 
which  is  secured 
a  hardened  steel 
plate,  which  in 
most  cases  acts 
directly  upon  the 
end  of  the  valve- 
stem. 

Another  form 
of  valve  lifter  is 
shown  in  Fig- 
ure 40,  in  which 
the  rocker  arm  is 
omitted,  the  cam 
operating  the  valve  through  the  medium  of  a 
plunger  rod  and  roller. 

Valve  Operating  Mechanism.  A  form  of 
valve  operating  mechanism  is  shown  in  Fig- 
ure 41,  in  which  both  the  inlet  and  exhaust- 
valves  are  operated  independently  by  means 
of  a  rocker-shaft  and  lifting  arms,  through 
the  medium  of  two  cam-rods  and  levers  shown 
at  the  right  of  the  drawing.  The  lifter-arm  and 
cam-rod  lever  of  the  inlet-valve  are  in  one 


FIG.  39 

Valve  lifter  and  roller  lever  with  hard- 
ened steel  lifter  plate. 


GAS  AND  OIL  ENGINE  HAND-BOOK      129 

piece,  and  work   free  on  the  end  of  the    rocker 
shaft. 

Valve  Stems,  Fit  of.     The  inlet  and  exhaust- 
valve  stems  should  not  be  a  very  close  fit  in  their 


FIG.  40 

Valve  lifter  with  cam  acting  directly  cm  the  lifter. 


guides.  If  the  fit  in  these  guides  is  made  too  close, 
when  the  valve-chamber  becomes  heated  the  con- 
sequent expansion  may  cause  the  valve- stem  to 
stick  in  the  guides,  and  leakage  of  the  valve  will 
result. 

The  valve  seats  are  in  some  engines  left  almost 
sharp,  being  not  more  than  one- sixteenth  of  an 
inch  wide  before  grinding. 

Valves,  Timing  of.  The  movement  of  the 
valves  should  always  be  timed  to  give  the  proper 
results.  This  is  an  important  point  to  remem- 
ber. The  cam  shaft  on  a  four-cycle  engine  is 


130      GAS  AND   OIL   ENGINE    HAND-BOOK 


usually   driven   by   the  two  to  one  gear  on  the 
crank  shaft,  and  if  for  any  reason  the  gears  are 

taken  apart  and 
put  together, 
even  if  only 
one  tooth  out  of 
place,  it  will 
throw  the  valve 
mechanism  out 
of  time. 

To  ascertain 
if  the  valves  of 


FIG.  41 

Valve  operating  mechanism,  showing  inlet 
and  exhaust-valves  and  lifter  rods. 


an  engine  are 
properly  timed, 
turn  the  fly- 
wheel  over 
slowly  and  no- 
tice at  what 

points  the  valves  open  and  close,  and  when  the 
ignition,  if  electric,  takes  place. 

The  exhaust-valve  should  open  when  about  five- 
sixths  of  the  stroke  is  completed  and  close  at  the 
end  of  the  next  stroke.  The  next  inward  stroke 
is  the  compression  stroke,  when  all  valves  should 
be  closed.  At  the  beginning  of  the  next  outward 
stroke  the  inlet-valve  should  be  slightly  open. 

If  the  engine  is  taken  to  pieces,  it  is  important 
that  a  tooth  of  the  gear  wheel  on  the  crank  shaft 
and  a  corresponding  space  of  the  gear  on  the 
cam  shaft  should  be  marked,  so  that  when  put 


GAS  AND  OIL  ENGINE   HAND-BOOK     131 

together  again  the  same  teeth  may  mesh  together, 
and  so  avoid  altering  the  throw  of  the  cams  and 
consequent  timing  of  the  valves. 

Viscosity  of  Oils.  The  figures  given  for  the 
viscosity  of  an  oil  denote,  in  seconds,  the  time 
taken  by  1,000  grains  of  oil  to  flow  through  a 
small  orifice  in  the  testing  apparatus  at  various 
temperatures. 

The  standard  usually  adopted  for  viscosity  is 
genuine  sperm  oil,  which  is  taken  as  100  at 
70  degrees  Fahrenheit. 

Water  Cooling  System.  The  pipes  should 
be  of  ample  capacity,  and  the  pipe  leading  from 
the  top  of  the  cylinder  jacket  to  the  upper  part 
of  the  water  tank  should  be  arranged  so  as  to  be 
as  short  as  possible,  and  any  necessary  bends 
should  be  as  large  as  possible. 

The  water  supply  should  enter  near  the  exhaust 
opening  and  leave  it  at  the  highest  point  of  the 
cylinder  jacket. 

The  water  required  in  the  tank  should  be  from 
20  to  25  gallons  per  horsepower,  and  the  quantity 
required  to  circulate  in  the  water  jacket  to  keep 
the  cylinder  cool  is  about  4j  gallons  per  horse- 
power. 

The  temperature  of  the  water  from  the  cylinder 
jacket  should  never  be  over  140  to  160  degrees 
Fahrenheit,  and  if  the  load  is  constant  this  may 
be  reduced,  but  be  never  less  than  100  degrees 
Fahrenheit. 


132     GAS  AND  OIL  ENGINE  HAND-BOOK 


If  the  temperature  of  the  cylinder  is  allowed 
to  exceed  400  degrees  Fahrenheit  lubrication  will 
be  difficult,  and  if  the  cylinder  jacket  is  found  to 
be  much  hotter  than  the  water  in  the  tank,  the 
water  circulation  is  poor  from  scale  or  incrusta- 
tion, and  should  be  at  once  attended  to. 

Never  run  the  engine  without  water  in  the 
cylinder  jacket,  and  always  keep  the  level  of  the 


FIG.  42 

Proper  method  of  installing  water-tank  for  therino-syphou  or 
gravity  water  cooling  system. 

water  in  the  tank  at  least  six  inches  above  the 
upper  pipe. 

Figure  42  shows  the  proper  manner  of  connect- 
ing the  water  tank  to  the  cylinder  jacket.  The 
tank  should  be  connected  to  the  engine  with 


GAS  AND  OIL   ENGINE   HAND-BOOK     133 

short  lengths  of  rubber  hose  in  the  piping  to 
prevent  any  joints  or  connections  working  loose 
from  the  engine  vibration. 

The  object  of  the  water  is  not  to  keep  the 
cylinder  cold,  but  simply  cool  enough  to  prevent 
the  lubricating  oil  from  burning.  The  hotter  the 
cylinder  with  effective  lubrication  the  more  power 
the  engine  will  develop. 

It  should  be  remembered  that  a  hot  engine  is 
the  more  economical  in  fuel. 

Water-jackets.  The  thickness  of  the  water- 
jacket  space  around  the  cylinder  of  a  gas  or  oil 
engine  should  not  be  less  than  one-eighth  of  the 
bore  of  the  cylinder,  while  the  water  space  sur- 
rounding the  head  of  the  combustion  chamber  of 
the  cylinder  should  not  be  less  than  one-sixth  of 
the  cylinder  bore. 

Bosses  for  pipe  connections  to  the  water-jacket 
outlet  should  always  be  placed  at  the  highest 
point  of  the  jacket,  so  as  to  prevent  an  air  space 
being  formed  above  the  outlet  of  the  jacket. 
Steam  will  be  formed  in  this  space,  and  with 
a  gravity  or  thermal-syphon  system  is  liable 
to  blow  or  force  the  water  out  of  the  cylinder 
jacket. 

To  obtain  the  greatest  degree  of  fuel  economy 
and  engine  efficiency  the  jacket  water  should  be 
always  of  a  temperature  slightly  under  the  boiling 
point  of  water.  A  cool  water-jacket  is  a  sign  of 
an  inefficient  engine. 


134     GAS  AND  OIL  ENGINE  HAND-BOOK 

Water-jacket  Circulation.     Figure  43  shows 
the  proper  manner  of  making  the  water-jacket 


FIG.  43 

Water-circulation  through  the  cylinder  and  valve  chamber  of  a 
gas  or  oil  engine. 


pipe  connections  when  the  cooling  water  is  taken 
from  a  hydrant. 

The  water  from  the  inlet-pipe  enters  the 
bottom  of  the  cylinder  near  the  combustion 
chamber,  passing  around  the  valve  chamber  and 
out  through  the  upper  pipe  into  the  funnel  at  the 
top  of  the  waste  pipe.  A  connection  should  be 
made  into  the  waste  pipe  from  the  bottom  of  the 


GAS  AND  OIL  ENGINE  HAND-BOOK      135 

water-jacket  as  shown,  so  as  to  enable  the  jacket 
water  to  be  drawn  off  in  cold  weather. 

Water-jacket,  Draining  the.  During  cold 
weather  always  close  the  tank  valves  and  open 
the  drain  cock  so  as  to  drain  all  the  water  from 
the  water-jacket  and  the  pipes  leading  from  the 
water-jacket  to  the  tank,  as  a  freeze-up  in  the 
water-jacket  would  be  sure  to  injure  the  cylinder 
jacket  and  possibly  ruin  it.  It  is  a  good  rule 
during  the  cold  weather  to  shut  off  the  water 
from  the  cooling  tank  and  drain  the  cylinder 
jacket  from  three  to  five  minutes  before  shutting 
the  engine  down,  thereby  making  sure  that  all 
traces  of  water  are  out  of  the  cylinder  jacket  and 
pipes.  Also  in  starting  the  engine  in  cold 
weather  it  is  best  not  to  turn  on  the  water  until 
the  engine  has  been  running  from  three  to  five 
minutes. 

Water-jacket,  Testing  of.  The  water-jackets 
of  cylinders  or  valve-chambers  should  be  all 
tested  by  air  pressure  to  at  .least  120  pounds 
pressure  per  square  inch  before  the  piston  is  put 
into  the  cylinder. 


136     GAS  AND   OIL  ENGINE   HAND-BOOK 


TABLES 


DENSITY  AND  SPECIFIC  GRAVITY  EQUIVALENTS. 


j  Baume" 

Specific  Gravity 

Baum6 

Specific  Gravity 

Baume 

Specific  Gravity 

i  10° 

1.0000 

37° 

0.8395 

64° 

.7423 

11° 

0.9930 

38° 

.8346 

65° 

.7205 

12° 

.9861 

39° 

.8299 

66° 

.7168 

13° 

.9791 

40° 

.8251 

67° 

.7133 

14° 

.9722 

41° 

.8204 

68° 

.7097 

15° 

.9658 

42° 

.8157 

69° 

.7061 

16° 

.9594 

43° 

.8110 

70° 

.7025 

i  17° 

.9530 

44° 

.8063 

71° 

.6990 

:    18° 

.9466 

45° 

.8017 

72° 

.6956 

!   19° 

.9402 

46° 

.7971 

73° 

.6923 

20° 

.9339 

47° 

.7927 

74° 

.6889 

21° 

.9280 

48° 

.7883 

75° 

.6856 

22° 

.9222 

49° 

.7838 

76° 

.6823 

23° 

.9163 

50° 

.7794 

77° 

.6789 

24° 

.9105 

51° 

.7752 

78° 

.6756 

25° 

.9047 

52° 

.7711 

79° 

.6722 

26° 

.8989 

53° 

.7670 

80° 

.6689 

27° 

.8930 

54° 

.7628 

81° 

.6656 

28° 

.8872 

55° 

.7587 

82° 

.6619 

29° 

.8814 

56° 

.7546 

83° 

.6583 

30° 

.8755 

57° 

.7508 

84° 

.6547 

31° 

.8702 

58° 

.7470 

85° 

.6511 

32° 

.8650 

59° 

.7432 

86° 

.6481 

33° 

.8597 

60° 

.7394 

87° 

.6451 

34° 

.8544 

61° 

.7357 

88° 

.6422 

35° 

.8492 

62° 

.7319 

89° 

.6392 

!  36° 

.8443 

63° 

.7281 

90° 

.6363 

The  scale  generally  used  for  indicating  the  densities 
of  liquids  is  that  of  Baum6.  Zero  on  this  scale  corre- 
sponds to  the  density  of  a  solution  of  salt  of  specified 
proportions,  and  10  degrees  corresponds  to  the  density 
of  distilled  water  at  a  specified  temperature  or  to  a 
specific  gravity  of  unity.  The  portion  of  the  stem  of 
the  instrument  lying  between  these  two  points  is  di- 
vided into  ten  equal  parts  and  the  rest  of  the  stem  is 
divided  into  divisions  of  equal  size  up  to  90  degrees. 
Higher  numbers  indicate  lower  specific  gravities.  The 
above  table  shows  the  relation  existing  between  the 
Baum6  scale  and  specific  gravity  proper. 


GAS  AND   OIL  ENGINE   HAND-BOOK     137 

DIMENSIONS  OF  MACHINE  SCREWS. 


y 

11 

{j 

Diameter  of  Head. 

0 

a 

o 

^  *S 

G.JH 

1 

•a 

Number 
Screw. 

Threads 
Inch. 

Diamete: 
Body. 

Diamete 
Bottom  i 
Thread. 

No.ofTa 
for  Full 

s 

0  !>, 

o  o 

Flat  HCE 

Button 
Head. 

1  . 

i 

2 

56 

.084 

.053 

54 

44 

.16 

.15 

.13 

4 

36 

.110 

.062 

52 

34 

.22 

.20 

.17 

6 

32 

.136 

.082 

45 

28 

.27 

.25 

.22 

8 

32 

.163 

.109 

35 

19 

.32 

.29 

.26 

10 

32 

.189 

.135 

29 

11 

.37 

.35 

.30 

12 

24 

.216 

.144 

27 

2 

.43 

.39 

.34 

14 

20 

.242 

.156 

22 

1 

.48 

.44 

.39 

16 

20 

.268 

.182 

14 

.53 

.49 

.43 

18 

18 

.294 

.198 

8 

I! 

.58 

.52 

.47 

SAFE  WORKING  LOAD  OF  STEEL  BALLS. 


Diameter  of  ball. 

i 

T56 

I 

1  (? 

\ 

T\ 

1 

Working   load   per 

ball  in  pounds   .  . 

500 

780 

1125 

1530 

2000 

2530 

3125 

COMPOSITION  OF  ALLOYS. 


i 

1 
1 

d 
d 

N 

Antimony 

1 

Bismuth. 

Bronze,  for  Engine  bearings  . 

13 

110 

1 

Brass,    for   light   work,    other 
than  bearings. 

2 

1 

Bronze  flanges,  to  stand  braz- 
ing   

3? 

1 

1 

Genuine  Babbitt  metal  
Bronze,  for  bushings  

10 
16 

1 
130 

i 

1 

Metal,  to  expand  in  cooling  for 
patterns 

9 

0 

1 

Genuine  bronze 

9 

PO 

5 

9 

Spelter,  hard.     . 

1 

1 

Spelter,  soft  

1 

4 

3 

138     GAS  AND  OIL  ENGINE  HAND-BOOK 
STRENGTH  AND  WEIGHT  OF  MATERIALS. 


Material. 

* 

IffJ 

Resistance 
to  Compres- 
sion. 

PH  O 

|l 

Aluminum   
Brass—  Cast  
Sheet  

12,000 
18,000 
23,000 

10,000 
12  500 

.094 
.290 
295 

162 
504 
510 

Bronze  —  Aluminum  . 
Phosphor  .  . 
Copper  —  Cast  

60,000 
63,000 
18,000 

12,000 
12,000 
30,000 

!300 
313 

500 
530 
542 

Sheet  
Wire  
Gun  Metal   
Iron  —  Cast  

30,000 
50,000 
36,000 
16000 

40,000 

15,000 
100  000 

.317 
.317 
.290 
260 

548 
5<±3 
504 
450 

Malleable  .  .  . 
Wrought.  .  .  . 
Lead  

18,000 
50,000 
33,000 

80,000 
36,000 

.267 
.280 
.410 

460 
480 
711 

Steel  —  Tool  

100,000 

40,000 

.284 

490 

Cr.  Cast  
Mild. 

63,000 
60,000 

36,000 
36000 

284 
284 

490 
490 

C.  Rolled  .... 

63,000 

40,000 

.284 

490 

DIMENSIONS  OF  INVOLUTE  TOOTH   SPUR  GEARS. 


Diametrical 
Pitch. 

Circular 
Pitch. 

Width  of 
Tooth  on 
Pitch 
Line. 

Working 
Depth  of 
Tooth. 

Actual 
Depth  of 
Tooth. 

Clear- 
ance at 
Bottom 
of  Tooth. 

1 

3.142 

1.571 

2.000 

2.157 

0.157 

2 

1.571 

0.785 

1.000 

1.078 

0.078 

3 

1.047 

0.524 

0.667 

0.719 

0.052 

4 

0.785 

0.393 

0.500 

0.539 

0.039 

5 

0.628 

0.314 

0.400 

0.431 

0.031 

6 

0.524 

0.262 

0.333 

0.360 

0.026 

7 

0.447 

0.224 

0.286 

0.308 

0.022 

8 

0.393 

0.196 

0.250 

0.270 

0.019 

10     * 

0.314 

0.157 

0.200 

0.216 

0.016 

12 

0.262 

0.131 

0.167 

0.180 

0.013 

14 

0.224 

0.112 

0.143 

0.154 

0.011 

16 

0.196 

0.098 

0.125 

0.135 

0.009 

GAS  AND   OIL  ENGINE  HAND-BOOK      139 


MELTING  POINT  OF  METALS. 


Metal. 

Temperature 
in  Degrees 
Fahrenheit. 

Metal. 

Temperature 
in  Degrees 
Fahrenheit. 

Aluminum  

1160° 

Lead  

620° 

Bronze 

1690° 

Platinum 

3230° 

Copper  

1930° 

Silver  

1730° 

Gold 

1900° 

Steel. 

2400° 

Iron  —  Cast   
Wrought  . 

2000° 
3000° 

Tin  
Zinc  

445° 
780° 

WEIGHT  PER  CUBIC  FOOT  OF  SUBSTANCES. 


Materials. 

Weight 
in 
Pounds. 

Materials. 

Weight 
in 
Pounds. 

Ash   White  

38 

Mercury  

849 

Asphaltum   
Brick  —  Pressed.  .  . 
Common  .  . 
Cement—  Louisville 
Portland 
Cherry 

87 
150 
125 
50 
90 
42 

Mica  
Oak,  White  
Petroleum  
Pine—  White  
Northern  .  . 
Southern. 

183 
50 
55 
25 
34 
45 

Chestnut 

41 

Platinum.  . 

1342 

Clay,  Potter's  .... 
Coal  —  Anthracite. 

110 
93 

Quartz  
Resin.  .  .          .    . 

165 
69 

Bituminous 
Earth  

84 
95 

Sand  —  Dry  
Wet  

98 
140 

Ebony  

76 

Sandstone  

151 

Elm  

35 

Shale  

162 

Flint 

162 

Silver 

655 

Gold   Pure 

1204 

Slate 

175 

Hemlock  

25 

Spruce  

25 

Hickory   . 

53 

Sulphur.  . 

125 

Ivory 

114 

Svcamore  . 

37 

Lignum  Vitae 

83 

Tar.               

62 

Magnesium 

109 

Peat  

26 

Mahogany.  .  . 

53 

Walnut,  Black  .  .  . 

38 

Maple  

49 

Water  —  Distilled  . 

624 

Marble  

168 

Sea  

64 

140     GAS  AND  OIL  ENGINE  HAND-BOOK 


C^J  (N        <N  (M  (N  (N  (N  <T)  CO  CO  CO  CO  (M  (M  CO  «D 

coco      cococ?c?c?,H^^VVc?c?7^ 

°IO  O5  "^r-H  l>t>»OI>l—  llOCO*OCO'-H'-lt>'I> 
i—  IT—  1          CO          r—  lOl          i—  1          rH          i—  I  »-H  rH 


r-i  i-H  rH  i-(  (N  (M 


II 


CO  I-H  l>  00  CO  CO 

^-c^COCMCOOOCO^OOt^ 


i  . » 

w 


00i—  iC5COTt<        >.Ortirt<|>COl>OO5        i-H(M 
OOO5Oi—  iCO^'*»OO'-(C^COTfiiOOOOC"J 


00        i-H  t^  00  t^-  00  CO  00  >O  lO  CO  (M 
<<t!00'-HCOcOcO'<ti<MO-<tiCO<MOO 
cOTt^cOOOOCOcOO^OiOOiOOOOOi 


co  »o  »o  10 

CO   l>  l>          CO  (N  (M  <N 

10  CO  00  O  CO  CO  O5  CO  00  lO   »O   >O  CO  CO  CO 


GAS  AND  OIL  ENGINE  HAND-BOOK      141 


PROPERTIES  OF  COMPRESSED  AIR. 


Comp. 
in  At- 
mos- 
pheres. 

Mean 
Pressure. 

Temp,  in 
Degrees 
Fahr. 

Gauge 
Pres- 
sure. 

Absolute 
Pres- 
sure. 

Isother- 
mal Pres- 
sure. 

1 

0 

60 

0 

14.7 

1.68 

7.62 

145 

10 

24.7 

30.39 

2.02 

10.33 

178 

15 

29.7 

39.34 

2.36 

12.62 

207 

20 

34.7 

48.91 

2.70 

14.59 

234 

25 

39.7 

59.05 

3.04 

16.34 

252 

30 

44.7 

69.72 

3.38 

17.92 

281 

35 

49.7 

80.87 

3.72 

19.32 

302 

40 

54.7 

92.49 

4.06 

20.57 

324 

45 

59.7 

104.53 

4.40 

21.69 

339 

50 

64.7 

116.99 

4.74 

22  .  76 

357 

55 

69.7 

129.84 

5.08 

23.78 

375 

60 

74.7 

143.05 

5.42 

24.75 

389 

65 

79.7 

156.64 

5.76 

25.67 

405 

70 

84.7 

170.58 

6.10 

26.55 

420 

75 

89.7 

184.83 

DECIMALS  OF  AN  INCH  FOR  EACH 


#ta. 

Decimal. 

Fraction. 

£6s, 

Decimal. 

Fraction. 

1 

.03125 

17 

53125 

o 

.0625 

1-16 

18 

.5625 

9-16 

3 

.09375 

19 

.59375 

4 

.125 

1-8 

20 

.625 

5-8 

5 

.  15625 

21 

.  65625 

6 

.1875 

3-16 

22 

.6875 

11-16 

7 

.21875 

23 

.71875 

8 

.25 

1-4 

24 

.75 

3-4 

9 

.28125 

25 

.78125 

10 

.3125 

5-16 

26 

.8125 

13-16 

11 

.34375 

27 

.84375 

12 

.375 

3-8 

28 

.875 

7-8 

13 

.40625 

29 

.90625 

14 

.4375 

7-16 

30 

.9375 

15-16 

15 

.  46875 

31 

.96875 

16 

.5 

1-2 

32 

1. 

1 

142      GAS  AND  OIL  ENGINE   HAND-BOOK 


AVERAGE  WEIGHT  OF   SQUARE  HEAD  MACHINE  BOLTS 
PER  100. 


Length 
1^ 

P 

2M 

2M 

3  4 

3M 

P 
p 

ft 
P 

9 
10 
11 

12 
13 
14 
15 
16 
17 
18 
19 
20 

Diameter. 

X 

A 

H 

/* 

Yz 

Y* 

H 

% 

1 

4.0 
4.4 

4.7 
5.1 
5.4 
5.8 
6.1 
6.8 
7.5 
8.2 
8.9 
9.6 
10.3 
11.0 
11.7 
12.4 
13.1 

6.8 
7.3 
7.8 
8.4 
8.9 
9.5 
10.0 
11.1 
12.2 
13.2 
14.3 
15.4 
16.5 
17.6 
18.6 
19.7 
20.8 

10.6 
11.3 
12.0 
12.6 
13.8 
14.0 
14.7 
16.0 
17.4 
18.7 
20;0 
21.4 
22.8 
24.1 
25.9 
27.7 
29.5 
33.1 
36.7 
40.4 
44.0 

15.0 
16.1 
17.2 
18.2 
19.2 
20.2 
21.2 
23.2 
25.2 
27.2 
29.1 
31.2 
33.1 
35.1 
37.1 
39.1 
41.0 
45.0 
49.0 
53.0 
57.0 

23.9 
25.1 
26.3 
27.7 
29.0 
30.4 
31.8 
34.7 
37.5 
40.2 
43.0 
45.7 
48.4 
51.2 
54.0 
56.7 
59.4 
64.8 
70.3 
75.8 
81.3 
86.7 
92  2 

40.5 
42.7 
44.8 
47.0 
49.2 
51.4 
53.5 
57.9 
62.3 
66.7 
71.0 
75.4 
79.8 
84.1 
88.5 
92.9 
97.2 
106.0 
114  7 
123.5 
132.2 
140.7 
149.2 
157.6 
166.1 
174.6 
183.1 
191.5 
200.0 

70.0 
73.1 
76.2 
79.3 
82.4 
85.5 
88.7 
95.0 
101.2 
107.5 
113.7 
120.0 
126.2 
132.5 
138.7 
145.0 
151.2 
163.7 
176.2 
188.7 
201.0 
213.4 
225  9 
238.3 
250.8 
263.2 
275.6 
288.1 
300.5 

'i2o!5 

124.7 
128.9 
137.4 
145.8 
159.2 
167.7 
176.1 
184.6 
193.0 
201.4 
209.9 
218.3 
240.2 
257.1 
273.9 
290.0 
307.7 
324.5 
341.4 
358.3 
375.2 
392.0 
408.9 
425.8 

'l85!6 
196.0 
207.0 
218.0 
229.0 
240.0 
251.0 
262.0 
273  0 
284.0 
295.0 
317.0 
339.0 
360.0 
382.0 
404.0 
426.0 
448.0 
470.0 
492.0 
514.0 
536.0 
558.0 

97.7 
103.1 
108.6 
114.1 
119.5 
125.0 



Per  Inch 
Addi- 
tional. 

1.4 

2.2 

3.6 

4.0 

5.5 

8.5 

12.4 

16.9 

22.0 

APPROXIMATE  WEIGHT   OP   NUTS  AND  BOLT  HEADS, 
IN  POUNDS. 


Diameter  of  Bolt 

in  Inches. 

M 

•fs 

H 

ITB 

Yz 

y* 

M 

Weight  of  Hexagon  1 
Nut  and  Head...  f 

.017 

.042 

.057 

.109 

.128 

.267 

.43 

Weight  of  Square 
Nut  and  Head...  [ 

.021 

.049 

.069 

.120 

.164 

.320 

.55 

Diameter  of  Bolt 

in  Inches. 

H 

l/€ 

*" 

I/a 

2^ 

Weight  of  Hexagon  j 
Nut  and  Head.,  f 

.73 

1.10 

2.14 

3.78 

5.6 

8.75 

17.0 

Weight  of  Square  I 
Nut  and  Head.  .  .  f 

.88 

1.31 

2.56 

4.42 

7.0 

10.5 

21.0 

GAS  AND  OIL  ENGINE  HAND-BOOK     143 


COPPER  WIRE  GAUGE  TABLE. 


1 

Size. 

Weight  and 
Length. 

Resistance. 

a 

p 

• 

*"*  LJ  c5 

£H 

. 

fc 

8> 

II 

111 

OJO 

+3    3 

Oj   P 

ii 

!• 

3)  W 

fi 

i 

CH 

pL.3  ^  £3 

o  0  <u 

®  0 

^30 

.d  o 

o 

P.  2 

wQo§ 

OS 

feO 

OPk 

0000 

.460 

211600.0 

639.60 

1.564 

.051 

19929.7 

.0000785 

000 

.409 

167804.9 

507.22 

1.971 

.063 

15804.9 

.000125 

00 

.364 

133079.0 

402.25 

2.486 

.080 

12534.2 

.000198 

0 

.324 

105592.5 

319.17 

3.133 

.101 

9945.3 

.000315 

.289 

83694.49 

252.98 

3.952 

.127 

7882.8 

.000501 

2 

.257 

66373.22 

200.63 

4.994 

.160 

6251.4 

.000799 

8 

.229 

52633.53 

159.09 

6.285 

.202 

4957.3 

.001268 

4 

204 

41742.57 

126.17 

7.925 

.254 

3931.6 

.002016 

5 

.181 

33102.16 

100.05 

9.995 

.321 

3117.8 

.003206 

6 

.162 

26250.48 

79.34 

12.604 

.404 

2472.4 

.005098 

7 

.144 

20816.72 

62.92 

15.893 

.509 

1960.6 

.008106 

8 

.128 

16509.68 

49.90 

20.040 

.643 

1555.0 

.01289 

9 

.114 

13094.22 

39.58 

25.265 

.811 

1233.3 

.02048 

10 

.101 

10381.57 

31.38 

31.867 

1.023 

977.8 

.03259 

11 

.090 

8234.11 

24.89 

40.176 

1.289 

775.6 

.05181 

12 

.080 

6529.93 

19.74 

50.659 

1.626 

615.02 

.08237 

13 

.071 

5178.39 

15.65 

63.898 

2.048 

488.25 

.13087 

14 

,064 

4106.75 

12.41 

80.580 

2.585 

386.80 

.20830 

15 

.057 

3256  76 

9.84 

101.626 

3.177 

306.74 

.33133 

16 

.050 

2582.67 

7.81 

128.041 

4.582 

243.25 

.52638 

17 

.045 

2048.19 

6.19 

161.551 

5.183 

192.91 

.83744 

18 

.040 

1624.33 

4.91 

203.666 

6.536 

152.99 

1.3312 

19 

.035 

1252.45 

3.786 

264.136 

8.477 

117.96 

2.2392 

20 

031 

1021.51 

3.086 

324.045 

10.394 

96.21 

3.3438 

21 

.028 

810.09 

2.448 

408.497 

13.106 

76.30 

5.3539 

22 

.025 

642.47 

1.942 

514.933 

16.525 

60.51 

8.5099 

23 

.022 

509.45 

1.539 

649.773 

20.842 

47.98 

13.334 

24 

.020 

404.01 

1.221 

819.001 

26.284 

28.05 

21.524 

25 

.017 

320.41 

.967 

1034.126 

33.135 

80.18 

34.298 

26 

.015 

254.08 

.768 

1302.083 

41.789 

23.93 

54.410 

27 

.014 

201.49 

.608 

1644.737 

52.687 

18.98 

86.657 

28 

.012 

159.79 

.484 

2066.116 

-  66.445 

15.05 

137.283 

29 

.011 

126.72 

.384 

2604  .  167 

83.752 

11.94 

218.104 

30 

.010 

100.50 

.302 

3311.258 

105.641 

9.466 

349.805 

31 

.0089 

79.71 

.239 

4184.100 

133.191 

7.508 

557.286 

32 

.0079 

63.20 

.190 

52(53.158 

168.011 

5.952 

884.267 

33 

.0070 

50.13 

.151 

6622.517 

211.820 

4.721 

1402.78 

34 

.0063 

39.74 

.121 

8264.463 

267.165 

3.743 

2207.98 

35 

.0056 

31.52 

.094 

10638.30 

336.81 

2.969 

3583.12 

36 

.0050 

25.00 

.075 

13333.33 

424.65 

2.355 

5661.71 

37 

.0044 

19.83 

.060 

16666.66 

535.33 

1.868 

8922.20 

38 

.0039 

15.72 

.045 

22222.22 

675.22 

1.481 

15000.5 

39 

.0035 

12.47 

.038 

26315.79 

851.789 

1.174 

22415.5 

40 

.0031 

9.88 

.030 

33333.331074.11 

.931 

35803.8 

144      GAS  AND  OIL   ENGINE   HAND-BOOK 


SQUARES  AND  SQUARE  ROOTS  OF  NUMBERS  FROM  1  TO  100. 


Nos. 

Squares. 

Square 
Root. 

NOS. 

Squares. 

Square 
Root. 

1 

1 

1.000 

51 

2601 

7.141 

2 

4 

1.414 

52 

2704 

7.211 

3 

9 

1.732 

53 

2809 

7.280 

4 

16 

2.000 

54 

2916 

7.349 

5 

25 

2.236 

55 

3025 

7.416 

6 

36 

2.449 

56 

3136 

7.483 

7 

49 

2.646 

57 

3249 

7.550 

8 

64 

2.8*8 

58 

3364 

7.616 

9 

81 

3.000 

59 

3481 

7.681 

10 

100 

3.162 

60 

3600 

7.746 

11 

121 

3.317 

61 

3721 

7.810 

12 

144 

3.464 

62 

3844 

7.874 

13 

169 

3.606 

63 

3969 

7.937 

14 

196 

3.74:3 

64 

4096 

8.000 

15 

225 

3.873 

65 

4225 

8.062 

16 

256 

4.000 

66 

4356 

8.124 

17 

289 

4.1*3 

67 

4489 

8.185 

18 

324 

4.243 

68 

4624 

8.246 

19 

361 

4.359 

69 

4761 

8.3(.7 

20 

400 

4.472 

70 

4900 

8.367 

21 

441 

4.583 

71 

5041 

8.426 

22 

484 

4.690 

72 

5184 

8.485 

23 

529 

4.796 

73 

5329 

8.544 

24 

576 

4.899 

74 

5476 

8.602 

25 

625 

5.000 

75 

5625 

8.660 

26 

676 

5.099 

76 

5776 

8.718 

27 

729 

5.196 

77 

5929 

8.775 

28 

784 

5.292 

78 

6084 

8.832 

29 

841 

5.385 

79 

6241 

8.888 

30 

900 

5.477 

80 

6400 

9.944 

31 

961 

5.568 

81 

6561 

9.000 

32 

1024 

5.657 

82 

6724 

9.055 

33 

1089 

5.745 

83 

6889 

9.110 

34 

1156 

5.831 

84 

7056 

9.1(55 

35 

1225 

5.916 

85 

7225 

9.220 

36 

1296 

6.000 

86 

7396 

9.274 

37 

1369 

6.083 

87 

7569 

9.327 

38 

1444 

6.164 

88 

7744 

9.381 

39 

1521 

6.245 

89 

7921 

9.434 

40 

1600 

6.325 

90 

8100 

9.487 

41 

1681 

6.403 

91 

8281 

9.539 

42 

1764 

6.481 

92 

8464 

9.592 

43 

1849 

6.557 

93 

8649 

9.644 

44 

1936 

6.633 

94 

8836 

9.695 

45 

2025 

6.708 

95 

9025 

9.747 

46 

2116 

6.782 

96 

9216 

9.798 

47 

2209 

6.856 

97 

9409 

9.849 

48 

2304 

6.928 

98 

9604 

9.900 

49 

2401 

7.000 

99 

9801 

9.^50 

to 

2500 

7.071 

100 

10000 

10.000 

GAS  AND  OIL  ENGINE  HAND-BOOK     145 


AREAS  AND  CIRCUMFERENCES  OF  CIRCLES  FROM  0.05  TO 
8.80,  ADVANCING  BY  ^  OF  ONE  INCH. 


Diam. 

Area. 

Circum. 

Diam. 

Area. 

Circum. 

.05 

.0019 

.16 

2.15 

3.63 

6.75 

.10 

.0078 

.31 

2.20 

3.80 

6.91 

.15 

.017 

.47 

2.25 

3.98 

7.07 

.20 

.031 

.63 

2.30 

4.15 

7.22 

.25 

.049 

.78 

2.35 

4.34 

7.38 

.30 

.070 

.94 

2.40 

4.52 

7.54 

.35 

.096 

1.09 

2.45 

4.71 

7.69 

.40 

.12 

1.26 

2.50 

4.91 

7.85 

.45 

.16 

1.41 

2.55 

5.11 

8.01 

.50 

.19 

1.57 

2.60 

5.31 

8.17 

.55 

.24 

1.73 

2.65 

5.56 

8.32 

.60 

.28 

1.88 

2.70 

5.72 

8.48    - 

.65 

.33 

2.04 

2.75 

5.94 

8.64 

.70 

.38 

2.19 

2.80 

6.16 

8.79 

.75 

.44 

2.36 

2.85 

6.38 

8.95 

.80 

.50 

2.51 

2.90 

6.60 

9.11 

.85 

.57 

2.67 

2.95 

6.83 

9.27 

.90 

.64 

2.83 

3.00 

7.07 

9.42 

.95 

.71 

2.98 

3.05 

7.31 

9.58 

.00 

.78 

3.14 

3.10 

7.55 

9.74 

.05 

.86 

3.29 

3.15 

7.79 

9.89 

.10 

.95 

3.46 

3.20 

8.04 

10.05 

.15 

.03 

3.61 

3.25 

8.29 

10.21 

.20 

.13 

3.77 

3.30 

8.55 

10.37 

.25 

.23 

3.93 

3.35 

8.81 

10.52 

.30 

.33 

4.08 

3.40 

9.08 

10.68 

.35 

.43 

4.24 

3.45 

9.35 

10.84 

.40 

.54 

4.39 

3.50 

9.62 

10.99 

.45 

.65 

4.56 

3.55  . 

9.89 

11.15 

.50 

.77 

4.71 

3.60 

10.18 

11.31 

1.55 

.89 

4.87 

3.65 

10.46 

11.47 

1.60 

2.01 

5.03 

3.70 

10.75 

11.62 

1.65 

2.14 

5.18 

3.75 

11.04 

11.78 

.70 

2.27 

5.34 

3.80 

11.34 

11.94 

.75 

2.40 

5.49 

3.85 

11.64 

12.09 

.80 

2.54 

5.65 

3.90 

11.94 

12.25 

.85 

2.69 

5.81 

3.95 

12.25 

12.41 

.90 

2.84 

5.97 

4.00 

12.57 

12.57 

.95 

2.99 

6.13 

4.05 

12.88 

12.72 

2.00 

3.14 

6.28 

4.10 

13.20 

12.88 

2.05 

3.30 

6.44 

4.15 

13.53 

13.04 

2.10 

3.46 

6.59 

4.20 

13.85 

13.19 

146     GAS  AND  OIL  ENGINE  HAND-BOOK 


Diam. 

Area. 

Circum. 

Diam. 

Area. 

Circum. 

4.25 

14.19 

13.35 

6.45 

32.67 

20.26 

4.30 

14.52 

13.51 

6.50 

33.18 

20  .  42 

4.35 

14.86 

13.66 

6.55 

33.69 

20.58 

4.40 

15.20 

13.82 

6.60 

34.21 

20.73 

4.45 

15.55 

13.98 

6.65 

34.73 

20.89 

4.50 

15.90 

14.14 

6.70 

35.26 

21.05 

4.55 

16.25 

14.29 

6.75 

35.78 

21.20 

4.60 

16.62 

14.45 

6.80 

36.32 

21.36 

4.65 

16.98 

14.61 

6.85 

36.85 

21.52 

4.70 

17.35 

14.76 

6.90 

37.39 

21.68 

4.75 

17.73 

14.92 

6.95 

37.94 

21.83 

4.80 

18.09 

15.08 

7.00 

38.48 

21.99 

4.85 

18.47 

15.24 

7.05 

39.04 

22.15 

4.90 

18.86 

15.39 

7.10 

39.59 

22.30 

4.95 

19.24 

15.55 

7.15 

40.15 

22.46 

5.00 

19.63 

15.71 

7.20 

40.71 

22.62 

5.05 

20.03 

15.86 

7.25 

41.28 

22.78 

5.10 

20.43 

16.02 

7.30 

41.85 

22.93 

5.15 

20.84 

16.18 

7.35 

42.43 

23.09 

5.20 

21.23 

16.34 

7.40 

43.01 

23.25 

5.25 

21.65 

16.49 

7.45 

43.59 

23.40 

5.30 

22.06 

16.65 

7.50 

44.18 

23.56 

5.35 

22.48 

16.81 

7.55 

44.77 

23.72 

5.40 

22.90 

16.96 

7.60 

45.36 

23.88 

5.45 

23.33 

17.12 

7.65 

45.96 

24.03 

5.50 

23.76 

17.28 

7.70 

46.57 

24.19 

5.55 

24.19 

17.44 

7.75 

47.17 

24.35 

5.60 

24.63 

17.59 

7.80 

47.78 

24.50 

5.65 

25.07 

17.75 

7.85 

48.39 

24.66 

5.70 

25.52 

17.91 

7.90 

49.02 

24.82 

5.75 

25.97 

18.06 

7.95 

49.64 

24.97 

5.80 

26.42 

18.22 

8.00 

50.26 

25.13 

5.85 

26.88 

18.38 

8.05 

50.89 

25.29 

5.90 

27.34 

18.54 

8.10 

51.53 

25.43 

5.95 

27.80 

18.69 

8.15 

52.17 

25.60 

6.00 

28.27 

18.85 

8.20 

52.81 

25.76 

6.05 

28.75 

19.01 

8.25 

53.46 

25.92 

6.10 

29.22 

19.16 

8.30 

54.11 

26.07 

6.15 

29.70 

19.32 

8.35 

54.76 

26.23 

6.20 

30.19 

19.48 

8.40 

55.42 

26.39 

6.25 

30.68 

19.63 

8.45 

56.08 

26.55 

6.30 

31.17 

19.79 

8.50 

56.74 

26.70 

6.35 

31.67 

19.95 

8.75 

60.13 

27.49 

6.40 

32.17 

20.11 

8.80 

60.82 

27.65 

GAS  AND  OIL  ENGINE   HAND-BOOK      147 


DIMENSIONS  OF  CAP  SCREWS. 


Hexagon 
Head. 

Square 
Head. 

i 

o 

o  a 

w 

1 

Diametei 
Screw. 

Number 
Threads 
Inch. 

Short 
Diameter. 

'Long 
Diameter. 

Short 
Diameter. 

Long 
Diameter. 

Philister 

Round  H 

i 

20 

A 

i 

:76 

I 

i 

A 

iV 

18 

1 

li 

i 

fl 

T6 

& 

§ 

16 

T9Tf 

fl 

T9o 

|| 

A 

T?« 

14 

5 

If 

| 

11 

i 

i 

12 

| 

II 

| 

iiV 

f 

\  § 

fl) 

12 

JL  3 

ft 

H 

lLt 

1A 

it 

ii 

t? 

11 

i 

4 

11 

I 

i 

i 

10 

I8 

IA 

1 

ll?6 

1 

H 

i 

9 

11 

in 

1* 

111 

li 

1 

8 

li 

Il76 

li 

i« 

il 

H 

7 

If 

113 

11 

1H 

li 

7 

li 

Ill 

l| 

2A 

DIMENSIONS  OF  TAP-DRILLS  FOR  STANDARD  V-THREADS. 


o 

r-l 

** 

<B 

1 

|. 

2 

few 

4J    ° 

2 

^'d 

0  £ 

JS-S 

1)   p  T3 

£^ 

o 

§2 

sl 

HI 

11 

11 

i 

20 

.163 

a 

^ 

A 

18 

.216 

"sV 

r 

1 

16 

.267 

el 

A 

•1 

14 
12 

.314 
.356 

II 

II 
ii 

16 

12 
11 

.418 
.468 

f 

li 
ii 

| 

10 

.577 

H 

43 
64 

£ 

9 

.683 

H 

1! 

1 

8 

.784 

I1 

1! 

H 

7 

.878 

l.ft 

H 

7 

1.003 

i8 

I  A 

148     GAS  AND  OIL  ENGINE   HAND-BOOK 


CALORIFIC  POWER  OF  VARIOUS  FUELS  IN  BRITISH 
THERMAL  UNITS. 


Combustible. 

Calorific 
Power. 

Evapor- 
ative 
Power 
from 
and  at 
212°  F. 

Carbon 
Value. 

Carbon,  burned  to  carbonic  acid 
Carbon,  burned  to  carbonic  oxide 
Charcoal  from  wood   . 

14,500 
4,450 
12  000 

15.00 
4.61 
12  4 

1.000 
0.307 
0  827 

Coke 

13  000 

13  45 

0  896 

Coal,  bituminous,  average  
Coal,  anthracite,  average  
Coal,  Welsh,  average  
Creosote  or  tar  refuse  
Naphtha  refuse  

14,000 
15,000 
14,800 
17,400 
19  200 

14.48 
15.52 
15.31 
18.00 
19  86 

0.965 
1.035 
1.021 
1.199 
1.324 

Petroleum,  average  
Hydrogen  

20,000 
62,060 

20.68 
64.19 

1.379 
4.280 

Coal  gas,  average  

21,000 

21.72 

1.448 

Natural  gas  (Pennsylvania)  .... 
Olefiant  gas  

26,000 
21  343 

26.89 
2208 

1.793 
1  472 

Marsh  gas  

23,513 

24.32 

1  621 

Block  fuel 

15  000 

15  52 

1  035 

Sulphur  

4,000 

4.138 

0.276 

WEIGHT  PER  CUBIC   FOOT  AND  SPECIFIC  HEAT  OF 
VARIOUS  GASES. 


Name. 

Pounds 
per  Cubic 
Foot. 

Specific 
Heat. 

Marsh  gas  

.0447 

470 

Olefines  

.1174 

.332 

H  y  drogen 

00559 

2  406 

Carbon  monoxide 

0783 

173 

Nitrogen                

.0783 

173 

Carbon  dioxide 

1060 

171 

Oxygen  

.1060 

.155 

These  weights  are  for  the  gases  when  at  an  atmos- 
pheric pressure  of  14.7  Ib.  per  square  inch  and  a  tem- 
perature of  32  degrees  Fahrenheit.  The  specific  heat 
of  a  mixture  may  be  found  in  the  same  manner  as 


GAS  AND   OIL   ENGINE   HAND-BOOK     149 


the  weight,  by  multiplying  the  specific  heat  for  each  gas 
by  the  per  cent  contained  in  the  fuel  and  adding  the 
results.  The  weight  of  air  at  32  degrees  Fahrenheit  and 
at  a  pressure  of  14.7  Ib.  per  square  inch  is  .08082  pounds. 
The  specific  heat  of  air  at  constant  volume  is  .1688. 

HEAT  VALUES  OF  FUELS. 


B.  T.  U, 

B.  T.  U. 

Fuel. 

Per  Lb. 

Per  Cu.  Ft. 

Hydrogen  @  32°  F  

62,030 

348 

Carbon                    

14,500 

Carbon  monoxide  (CO)  
Penn.  heavy  crude  oil  
Caucasian  heavy  crude  oil  .... 
Caucasian  light  crude  oil   
Petroleum  refuse 

4,396 
20,736 
20,138 
22,027 
19,832 

539 

Anthracite  gas  .  .                  .... 

2,248 

Bituminous  gas             

3,484 

28-candlepower  ilium,  gas  .... 
1-9-            "               " 
15-            "               "         "   

950 
800 
620 

New  York  city  water-gas 

710  5  Ave 

London  coal  gas   .  .  

668 

Benzine   C«  Ho 

18  448 

Gasoline  and  its  vapor  

21,900 

690 

Ethylene  C2  H4   

21,430 

1,677 

Marsh  gas  (Methane)  CH4  
Nat   gas    Leechburg   Pa. 

23,594 

1,051 
1  051 

Nat   gas    Pittsburg   Pa. 

892 

Acetylene   Co  Ho 

21  492 

868 

Semi-water  gas 

185 

Producer  gas 

150 

150     GAS  AND  OIL  ENGINE   HAND-BOOK 


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O  00  t^  CO  CO  00  O  <M  CO  O 

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r-Hr-l^-I^HrH     <N  <N  <N  CO  CO 


OOt^COOCO 
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COI>OOOi 


GAS  AND  OIL  ENGINE  HAND-BOOK      151 


<N  <N  <N  C^  CO  COCOCOCOCO  CO  CO  CO  CO  * 


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152     GAS   AND  OIL   ENGINE   HAND-BOOK 


<M  CO  **  »O    CO  l>  00  Oi  O    i— i  <N  CO  -*  »O    CO 
Tti  TJH  rf  -^H  10    lO  tO  *O  *O  lO   LO 


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GAS  AND   OIL  ENGINE  HAND-BOOK      153 


i—  I  <N  CO  rfi  »O  CO  !>•  00  Oi  O  i—  i  <N  CO  **  iO  CO  t>-  00  Ci 
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154      GAS  AND  OIL  ENGINE  HAND-BOOK 


r-i  <M  CO  Tf<  iO  CO  1>  00  O5  O  i—  i  C^  CO  rfi  tO 
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GAS  AND  OIL  ENGINE   HAND-BOOK    155 


DIMENSIONS  OF  U.  S.  STANDARD  SCREW  THREADS, 
NUTS  AND  BOLT  HEADS. 

Recommended  by  the  Franklin  Institute  and  adopted 
by  the  Navy  Department  of  the  United  States,  by  the 
Railroad  Master  Mechanics  and  Master  Car-Builders 
Associations  and  by  many  of  the  prominent  engineering 
and  mechanical  establishments  of  the  United  States. 


Diameter 
Screw. 

Threads 
per  inch. 

Diameter 
at  root  of 
Thread. 

Diameter 
Screw. 

Threads 
per  inch. 

Diameter 
at  root  of 
Thread. 

~4 

20 

.185 

2 

43^ 

1.712 

5c 

18 

.240 

234 

43^ 

1.962 

3^ 

16 

.294 

21A 

4 

2.176 

7 

14 

.344 

2% 

4 

2.426 

/^ 

13 

.400 

3 

2.629 

9 

12 

.454 

334 

33^ 

2.879 

^ 

11 

.507 

3H 

334 

3.100 

% 

10 

.620 

m 

3 

3.317 

Y& 

9 

.731 

4 

3 

3.567 

1 

8 

.837 

434 

2J^ 

3.798 

7 

.940 

43^ 

2M 

4.028 

\\/ 

7 

1.065 

4M 

2/^ 

4.256 

J3X 

6 

.160 

5 

23^ 

4.480 

& 

6 

.284 

4.730 

ig 

5H 

.389 

53^ 

2^ 

4.953 

5 

.491 

534 

2% 

5.203 

iff 

5 

.616 

6 

234 

5.423 

Angle  of  the  thread  60°.  Flat  at  top  and  bottom  J  of 
the  pitch. 

NUTS  AND  BOLT  HEADS  are  determined  by  the  following 
rules,  which  apply  to  Square  and  Hexagon  Nuts  both: 

Short  diameter  of  rough  nut  =  1  %  X  diam.  of  bolt  -j- 
Jin. 

Short  diameter  of  finished  nut  =  1|  X  diam.  of  bolt 
+  iin. 

Thickness  of  rough  nut  =  diam.  of  bolt. 

Thickness  of  finished  nut  =  diam.  of  bolt  —  |  in. 

Short  diameter  of  rough  head  =  1£  X  diam.  of  bolt 
+  tin. 

Short  diameter  of  finished  head  =  1£  X  diam.  of  bolt 
+  iin. 

Thickness  of  rough  head  =  J  short  diam.  of  head. 

Thickness  of  finished  head  =  diam.  of  bolt  —  |  in. 

The  long  diameter  of  a  hexagon  nut  may  be  obtained 
by  multiplying  the  short  diameter  by  1.155,  and  the 
long  diameter  of  a  square  nut  by  multiplying  the  short 
diameter  by  1.414. 


156     GAS  AND   OIL  ENGINE  HAND-BOOK 


CIRCUMFERENCES  OF  CIRCLES  FROM  0.01  TO  80.9 
ADVANCING  BY  IOTHS. 


_l 

.0 

.1 

.2 

.3 

.4 

.5 

.6 

.7 

.8 

.9 

1 

0 

.00 

.31 

.62 

.94 

1.25 

1.57 

1.88 

2.19 

2.51 

2.82 

0 

1 

3.14 

3.45 

3.77 

4.08 

4.39 

4.71 

5.02 

5.34 

5.65 

5.96 

1 

2 

6.28 

6.59 

6.91 

7.22 

7.53 

7.85 

8.16 

8.48 

8.79 

9.11 

2 

3 

9.42 

9.74 

10.05 

10.36 

10.68 

10.99 

11.30 

11.62 

11.93 

12.25 

3 

4 

12.56 

12.88 

13.19 

13.50 

13.82 

14.13 

14.45 

14.76 

15.08 

15.39 

4 

5 

15.70 

16.02 

16.33 

16.65 

16.96 

17.27 

17.59 

17.90 

18.22 

18.53 

5 

6 

18.84 

19.16 

19.47 

19.79 

20.10 

20.42 

20.73 

21.04 

21.36 

21.67 

6 

7 

21.99 

22.30 

22.61 

22.93 

23.24 

23.56 

23.87 

24.19 

24.50 

24.81 

7 

8 

25.13 

25.44|25.76 

26.07 

26.38 

26.70 

27.01 

27.33 

27.64 

27.96 

8 

9 

28.27 

28.58  28.90 

29.21 

29.53 

29.34 

30.15 

30.47 

30.78 

31.10 

9 

10 

31.41 

31.73 

32.04 

32.35 

32.67 

32.98 

33.30 

33.61 

33.92 

34.24 

10 

11 

34.55 

34.87 

35.18 

35.50 

35.81 

36.12 

36.44 

36.75 

37.07 

37.38 

11 

12 

37.69 

38.01  38.32 

38.64 

38.95 

39.27 

39.58 

39.89 

40.21 

40.52 

12 

13 

40.84 

41.1541.46 

41.78 

42.09 

42.41 

42.72 

43.03 

43.35 

43.66 

13 

14 

43.98 

44.29  44.61 

44.92 

45.23 

45.55 

45.86 

46.18 

46.49 

46.80 

14 

15 

47.12 

47.43 

47.75 

48.06 

48.38 

48.69 

49.00 

49.32 

49.63 

49.95 

15 

If. 

50.26 

50.57 

50.89 

51.20 

51.52 

51.83 

52.15 

52.46 

52.78 

53.09 

16 

17 

53.40 

53.72 

54.03 

54.35 

54.65 

54.97 

55.29 

55.60 

55.92 

56.23 

17 

IS 

56.54 

56.8657.17 

57.49 

57.80 

58.11 

58.43 

58.74 

59.06 

59.37 

18 

19 

59.69 

60.0060.31 

60.63 

60.94 

61.26 

61.57 

61.88 

62.20 

62.51 

19 

20 

62.83 

63.14 

63.46 

63.77 

64.08 

64.40 

64.71 

65.03 

65.34 

65.65 

20 

12 

65.97 

66.28 

66.60 

66.91 

67.22 

67.54 

67.85 

68.17 

68.48 

68.80 

21 

22 

69.11 

69.4269.74 

70.05 

70.37 

70.68 

71.00 

71.31 

71.62 

71.94 

22 

23 

72.25 

72.57  72.88 

73.19 

73.51 

73.82 

74.14 

74.45 

74.76 

75.08 

23 

24 

75.39 

75.71  76.02 

76.34|  76.65 

76.96 

77.28 

77.59 

77.91 

78.22 

24 

25 

78.54 

78.85 

79.16 

79.48 

79.79 

80.11 

80.42 

80.73 

81.05 

81.36 

25 

2G 

81.68 

81.99 

82.30 

82.62 

82.93 

83.25 

83.56 

83.88 

84.19 

84.50 

26 

27 

84.82 

85.13 

85.45 

85.76 

86.07 

86.39 

86.70 

87.02 

87.33 

87.65 

27 

28 

87.96 

88.27 

88.59 

88.90 

89.22 

89.53 

89.84 

90.16 

90.47 

90.79 

28 

29 

91.10 

91.42 

91.73 

92.04 

92.36 

92.67 

92.99 

93.30 

93.61 

93.93 

29 

30 

94.24 

94.56 

94.87 

95.19 

95.50 

95  81 

96.13 

96.44 

96.76 

97.07 

30 

31 

97.38 

97.70 

98.01 

98.33 

98.64 

98.96 

99.27 

99.58 

99.90 

100.2 

31 

32 

100.5 

100.8 

101  1 

101.4 

101.7 

102.1 

102.4 

102.7 

103.0 

103.3 

32 

33 

103.6 

103.9 

104.3 

104.6 

104.9 

105.2 

105.5 

105.8 

106.1 

106.5 

33 

34 

106.8 

107.1 

107.4 

107.7 

108.0 

108.3 

108.6 

109.0 

109.3 

109.6 

34 

35 

109.9 

110.2 

110.5 

110.8 

111.2 

111.5 

111.8 

112.1 

112.4 

112.7 

35 

30 

113.0 

113.4 

113.7 

114.0 

114.3 

114.6 

114.9 

115.2 

115.6 

115.9 

36 

37 

116.2 

116.5 

116.8 

117.1 

117.4 

117.8 

118.1 

118.4 

118.7 

119.0 

37 

38 

119.3 

119.6 

120.0 

120.3 

120.6 

120.9 

121.2 

121.5 

121.8 

122.2 

38 

39 

122.5 

122.8 

123.1 

123.4 

123.7 

124.0 

124.4 

124.7 

125.0 

125.3 

39 

40 

125.6 

125.9 

126.2 

126.6 

126.9 

127.2 

127.5 

127.8 

128.1 

128.4 

40 

41 

128.8 

129.1 

129.4 

129.7 

130.0 

130.3 

130.6 

131.0 

131.3 

131.6 

41 

42 

131.91132.2 

132.5 

132.8 

133.2 

133.5 

133.8 

134.1 

134.4 

134.7 

42 

43 

135.0135.4 

135.7 

136.0 

136.3 

136.6 

136.9 

137.2 

137.6 

137.9 

43 

44 

138.2138.5 

138.8 

139.1 

139.4 

139.8 

140.1 

140.4 

140.7 

141.0 

44 

45 

141.3,141.6 

142.0 

142.3 

142.6 

142.9 

143.2 

143.5 

143.9 

144.2 

45 

GAS  AND  OIL  ENGINE  HAND-BOOK      157 


CIRCUMFERENCES  OF  CIRCLES — Continued. 


5 
.5 
Q 

.0 

.1 

.2 

.3 

.4 

.5 

.6 

.7 

.8 

.9 

1 

46 

144.5 

144.8 

145.1 

145.4 

145.7 

146.0 

146.3 

146.7 

147.0 

147.3 

46 

47 

147.6 

147.9 

148.3 

148.6 

148.9 

149.2 

149.5 

149.8 

150.1 

150.4 

47 

48 

150.7il51.1 

151.4 

151.7 

152.0 

152.3 

152.6 

152.9 

153.3 

153.6 

48 

49 

153.9154.2 

154.5 

154.8 

155.1 

155.5 

155.8 

156.1 

156.4 

156.7  49 

50 

157.0 

157.3 

157.7 

158.0 

158.3 

158.6 

158.9 

159.2 

159.5 

159.9 

50 

51 

160.2 

160.5 

160.8 

161.1 

161.4 

161.7 

162.1 

162.4 

162.7 

163.0 

51 

52 

163.3163.6 

163.9 

164.3 

164.6 

164.9 

165.2 

165.5 

165.8 

166.1 

52 

53 

1G6.5;166.8 

167.1 

167.4 

167.7 

168.0 

168.3 

168.7 

169.0 

169.3 

53 

54 

169.6169.9 

170.2 

170.5 

170.9 

171.2 

171.5 

171.8 

172.1 

172.4 

54 

55 

172.7 

173.1 

173.4 

173.7 

174.0 

174.3 

174.6 

174.9 

175.3 

175.6 

55 

56 

175.9 

176.2 

176.5 

176.8 

177.1 

177.5 

177.8 

178.1 

178.4 

178.7 

56 

57 

179.0179.3 

179.9 

180.0 

180.3 

180.6 

180.9 

181.2 

181.5 

181.9 

57 

58 

182.2182.5 

182.8 

183.1 

183.4 

183.7 

184.0 

184.4 

184.7 

185.0 

58 

59 

185.3185.6 

185.9 

186.2 

186.6 

186.9 

187.2 

187.5 

187.8 

188.1 

59 

60 

188.4 

188.8 

189.1 

189.4 

189.7 

190.0 

190.3 

190.6 

191.0 

191.3 

60 

61 

191.6 

191.9 

192.2 

192.5 

192.8 

193.2 

193.5 

193.8 

194.1 

194.4 

61 

G2 

194.7 

195.0 

195.4 

195.7 

196.0 

196.3 

196.6 

196.9 

197.2 

197.6 

62 

63 

197.9 

198.2 

198.5 

198.8 

199.1 

199.4 

199.8 

200.1 

200.4 

200.7 

63 

64 

201.0 

201.3 

201.6 

202.0 

202.3 

202.6 

202.9 

203.2 

203.5 

203.8 

64 

65 

204.2 

204.5 

204.8 

205.1 

205.4 

205.7 

206.0 

206.4 

206.7 

207.0 

65 

66 

207.3 

207.6 

207.9 

208.2 

208.6 

208.9 

209.2 

209.5 

209.8 

210.1 

66 

67 

210.4210.8 

211.1 

211.4 

211.7 

212.0 

212.3 

212.6 

213.0 

213.3 

67 

68 

213.6213.9214.2 

214.5 

214.8 

215.1 

215.5 

215.81  216.1 

216.4 

68 

69 

216.7 

217.0217.3 

217.7 

218.0 

218.3 

218.6 

218.9 

219.2 

219.5 

69 

70 

219.9 

220.2 

220.5 

220.8 

221.1 

221.4 

221.7 

222.1 

222.4 

222.7 

70 

71 

223.0 

223.3 

223.6 

223.9 

224.3 

224.6 

224.9 

225.2 

225.5 

225.8 

71 

72 

226.1 

226.5 

226.8 

227.1 

227.4 

227.7 

228.0 

228.3 

228.7 

229.0 

72 

73 

229.3229.6 

229.9 

230.2 

230.5 

230.9 

231.2 

231.5 

231.8 

232.1 

73 

74 

232.4  232.7 

233.1 

233.4 

233.7 

234.0 

234.3 

234.6 

234.9 

235.3 

74 

75 

235.6 

235.9 

236.2 

236.5 

236.8 

237.1 

237.5 

237.8 

238.1 

238.4 

75 

76 

238.7 

239.0 

239.3 

239.7 

240.0 

240.3 

240.6 

240.9 

241.2 

242.5 

76 

77 

241.9242.2 

242.5 

242.8 

243.1 

243.4 

243.7 

244.1 

244.4 

244.7 

77 

78 

245.0245.3 

245.6 

245.9 

246.3 

246.6 

246.9 

247.2 

247.5 

247.8 

78 

79 

248.1  248.5 

248.8 

249.1 

249.4 

249.7 

250.0 

250.3 

250.6 

251.0 

79 

80 

251.3251.6 

251.9   252.2 

252.5 

252.8 

253.2 

253.5    253.8 

254.1 

80 

Mensuration  of  Surface  and  Volume.  The 
area  of  a  rectangle  is  equal  to  the  length  X 
breadth. 

Area  of  a  triangle  is  equal  to  the  base  X  one- 
half  the  perpendicular  height. 

Diameter  of  a  circle  is  equal  to  the  radius  X  2. 


158     GAS  AND   OIL  ENGINE  HAND-BOOK 

Circumference  of  a  circle  is  equal  to  the  diam- 
eter X  3.1416. 

Area  of  a  circle  is  equal  to  the  square  of 
diameter  X  .7854. 

Area  of  a  sector  of  a  circle  is  equal  to  the  area 
of  the  circle  X  number  of  degrees  in  arc  -r-  360. 

Area  of  surface  of  a  cylinder  is  equal  to  the 
circumference  X  length,  plus  the  area  of  both 
ends. 

To  find  the  diameter  of  a  circle  having  a  given 
area:  Divide  the  area  by  .7854,  and  extract  the 
square  root. 

To  find  the  volume  of  a  cylinder:  Multiply 
the  area  of  the  section  in  square  inches  by  the 
length  in  inches,  this  equals  the  volume  in  cubic 
inches.  Cubic  inches  divided  by  1728  is  equal  to 
the  volume  in  cubic  feet  of  any  body. 

The  surface  of  a  sphere  is  equal  to  the  square 
of  diameter  X  3.1416. 

Volume  of  a  sphere  is  equal  to  the  cube  of 
diameter  X  .5236. 

The  side  of  an  inscribed  cube  is  equal  to  the 
radius  of  the  sphere  X  1.1547. 

The  area  of  the  base  of  a  pyramid  or  cone, 
whether  round,  square  or  triangular,  multiplied 
by  one-third  of  its  height  is  equal  to  the  volume. 

A  gallon  of  water  (United  States  Standard) 
weighs  8t  pounds  and  contains  231  cubic  inches. 


ADDENDUM 

Gas  Engine  Troubles.  For  those  who  have 
not  the  time  to  study  gas  engine  principles 
this  section  is  included. 

Many  of  the  troubles  are  due  to  the  opera- 
tor's ignorance  of  the  principles  of  operation, 
or  to  negligence  in  taking  care  of  the  engine. 

One  of  the  most  common  mistakes  is  trying  to 
make  the  engine  run  without  fuel.  The  opera- 
tor will  turn  the  starting  crank  until  out  of  breath 
when  he  will  suddenly  discover  that  the 
gasoline  tank  is  empty! 

A  gas  engine  will  not  run  without  gas,  but  it 
is  hard  to  get  this  simple  fact  fixed  permanently 
in  the  mind  of  the  operator. 

Another  trouble,  similar  to  the  empty  gaso- 
line tank,  is  trying  to  make  the  engine  run  with- 
out a  spark  to  ignite  the  compressed  charge. 
Sometimes  a  connection  in  the  wiring  will  break 
which  will  deceive  the  operator. 

A  short  circuit,  in  an  unexpected  place,  will  lead 
to  the  same  trouble. 

See  that  the  engine  gets  a  proper  charge,  then 
see  that  the  spark  is  heavy  enough  to  fire  it. 

Do  not  turn  the  starting  crank  or  fly  wheel 
until  patience  and  endurance  are  entirely  ex- 
pended. 

159 


160      GAS  AND  OIL  ENGINE  HAND-BOOK 

If  the  engine  does  not  start  promptly  in  four 
or  five  turns,  the  right  conditions  are  not  present 
and  the  operator  should  use  a  little  common 
sense  instead  of  so  much  muscle.  Correct  the 
faulty  conditions  and  the  engine  will  start  at 
once. 

The  simplicity  of  the  causes  leading  to  the 
above  mentioned  troubles  is  sufficient  reason  for 
their  existence. 

Oiling  a  Gas  Engine.  The  oiling  of  the 
engine  should  be  done  in  a  thorough  manner. 
Use  machine  oil  on  the  various  parts  of  the  en- 
gine, except  in  the  cylinder.  A  special  oil  for 
gas  engines  should  be  used  for  the  cylinders. 

Steam  cylinder  oil  is  not  well  adapted  to  a  gas 
engine  cylinder.  A  light  cylinder  oil,  of  high  fire 
test,  is  best  adapted  to  use  in  the  gas  engine 
cylinder.  Some  gas  engines  are  fitted  at  the 
wrist  pin  and  journal  bearings  with  grease  cups, 
which  should  be  filled  with  shafting  and  set  so 
as  to  feed  automatically. 

When  oil  and  grease  cups  are  filled  and  all 
bearing  parts  that  are  liable  to  wear  are  oiled, 
the  valve  stems  should  be  tried  by  lifting  the 
valve  from  its  seat  a  number  of  times  after  put- 
ting some  kerosene  oil  on  the  stem  with  an  oil 
can.  The  stems  should  be  frequently  examined 
and  kerosene  oil  used  occasionally  to  keep  them 
clean.  Never  use  ordinary  lubricating  oil  on 
them.  The  heat  simply  burns  it  and  leaves  a 


GAS  AND  OIL  ENGINE  HAND-BOOK       161 

gummy  deposit  on  the  stem  which  interferes  with 
the  free  movement  of  the  valve. 

It  is  said  that  oil  is  cheaper  than  machinery 
and  we  want  to  earnestly  emphasize  the  truth  of 
that  statement. 

It  should  be  good  oil,  however,  for  there  is  a 
great  difference  in  the  quality  of  oils,  and  good 
oil  only  can  be  considered  if  the  cost  of  the  ma- 
chine is  kept  in  mind. 

Some  of  the  so-called  lubricating  oils  on  the 
market  have  but  little  more  value  than  so  much 
water. 

It  is  not  only  a  question  of  economy  in  using 
a  good  lubricant  with  an  engine,  but  also  of  in- 
creasing the  net  power  for  effective  work. 
This  is  especially  true  with  the  gas  engine  for 
it  depends  on  the  oil  to  make  the  piston  and 
rings  tight  to  hold  both  the  compression  and  the 
high  pressure  of  the  explosion. 

The  most  accurate  job  of  machining  and  fit- 
ting of  the  cylinder,  piston  and  rings  would  not 
hold  these  pressures  without  a  film  of  good  gas  en- 
ine  oil  between  the  piston  and  the  cylinder  walls. 

The  importance  of  proper  lubrication  can 
hardly  be  overestimated  as  will  be  readily  ap- 
parent when  the  action  of  a  good  oil,  either  on 
the  cylinder  walls  or  in  a  properly  adjusted  bear- 
ing is  thoroughly  understood. 

A  good  oil  forms  an  almost  frictionless  film 
between  the  surfaces  of  the  piston,  rings  and 


162      GAS  AND  OIL  ENGINE  HAND-BOOK 

walls  of  the  cylinder,  or  between  the  shaft  and 
the  bearing  as  the  case  may  be,  and  thus  prevents 
the  metals  from  coming  in  direct  contact.  With- 
out direct  frictional  contact  there  is,  of  course, 
no  wear  or  deterioration  of  the  metals  so  long 
as  the  proper  condition  is  maintained,  hence  we 
must  conclude  that  the  natural  wear  we  figure 
on  in  the  life  of  any  machine  is  due  to  imperfect 
lubrication  a  portion  of  the  time. 

It  is  a  difficult  thing  to  maintain  a  perfect 
condition  at  all  times,  but  the  use  of  good  oil  and 
proper  attention  to  the  oiling  will  greatly  in- 
crease the  life  of  the  machine  to  say  nothing  of 
the  saving  of  repairs,  trouble  and  loss  of  time 
in  repairing,  etc. 

It  does  not  follow,  however,  that  an  excessive 
amount  of  oil  should  be  applied  as  is  often  done 
on  the  theory  that  if  a  little  is  good  more  is 
better.  When  too  much  oil  is  applied  the  sur- 
plus runs  out  of  the  bearing  and  is  often  wasted 
besides  making  a  greasy,  dirty  engine. 

In  the  case  of  the  cylinder  too  much  oil  will 
accumulate  and  burn  in  the  combustion  chamber, 
leaving  a  carbon  deposit  on  the  walls  of  the  com- 
pression space  besides  fouling  the  sparking 
mechanism  and  causing  a  disagreeable  smoke  at 
the  exhaust. 

Probably  the  worst  possible  result  of  a  too 
liberal  use  of  oil  is  the  danger  of  the  machine 
running  dry  between  spasmodic  oilings. 


GAS  AND  OIL  ENGINE  HAND-BOOK      163 

The  operator,  feeling  sure  that  he  has  used 
plenty  of  oil  to  last  a  considerable  length  of 
time  (which  he  has  if  it  had  been  properly  ap- 
plied) will  neglect  the  machine  and  overlook  the 
fact  that  only  a  limited  amount  of  oil  will  be  re- 
tained in  the  bearing. 

The  all-important  thing  in  perfect  lubrica- 
tion is  to  supply  a  good  oil  frequently  and  regu- 
larly, or  continuously  if  possible,  to  the  parts 
where  there  would  be  great  friction. 

Do  not  feel  content  in  seeing  that  the  oil  is 
flowing,  but  know  positively  that  it  is  going  to 
the  right  place. 

Many  fine  bearings  have  been  utterly  ruined 
by  the  oil  holes  and  channels  becoming  clogged 
so  that  the  oil,  though  freely  applied,  could  not 
reach  all  parts  of  the  bearing. 

Cylinders  and  the  more  important  bearings  of 
the  gas  engine  are  generally  oiled  by  pressure 
feed  and  sight  feed  oilers. 

These  oiling  devices  should  be  kept  in  first 
class  condition  and  set  to  feed  the  oil  in  the 
right  quantity  and  regularly  while  the  engine  is 
running. 

Ordinary  machine  oils  are  of  little  value  for 
gas  engines  because  the  fire  test  is  entirely  too 
low  to  stand  the  high  heat  of  the  cylinder  and 
piston. 

Use  a  good  gas  engine  oil,  feeding  it  constantly 
or  at  least  frequently  and  regularly,  but  do  not 


164      GAS  AND  OIL  ENGINE  HAND-BOOK 

be  wasteful,  keep  in  mind  the  old  adage  revised, 
Good  oil  is  cheaper  than  machinery. 

For  main  bearings  and  similar  places  it  is  very 
common  to  use  cup  grease  or  what  is  sometimes 
called  "hard  oil"  which  is  fed  or  forced  to  the 
bearing  by  a  special  grease  cup. 

As  the  bearing  warms  up  under  service  the 
grease  melts  and  produces  the  film,  similar  to 
liquid  oils,  to  prevent  wear  and  relieve  the  fric- 
tion. The  process  of  converting  the  grease  to 
an  oil  film,  being  somewhat  automatic,  is  a  good 
point  for  cup  grease  as  against  liquid  oil  for 
some  kinds  of  service,  but  do  not  forget  that  the 
quality  of  the  grease  to  be  used  is  just  as  impor- 
tant as  with  the  liquid  oils. 

Timing  the  Spark.  The  timing  of  the  spark 
is  of  much  greater  importance  than  was  realized 
for  many  years  after  the  gas  engine  came  into  use. 

Although  the  charge  under  compression  fires 
easily  and  burns  rapidly,  yet  it  requires  a  small 
period  of  time,  and  the  spark  must  occur  far 
enough  ahead  of  the  end  of  the  stroke  so  that 
the  charge  will  be  ignited  and  the  expansion  tak- 
ing place  when  the  piston  starts  on  its  power 
stroke.  If  the  spark  occurs  too  late  a  part  of 
the  effective  power  stroke  is  lost,  while  if  the 
spark  occurs  too  early  the  heat  expansion  begins 
before  the  piston  reaches  the  end  of  its  stroke. 
This  will  cause  the  engine  to  pound  or  perhaps 
stop,  if  the  ignition  occurs  very  much  too  early. 


GAS  AND  OIL  ENGINE  HAND-BOOK       165 

The  correct  time  for  the  spark  depends  en- 
tirely on  the  speed  of  the  engine.  At  high  speeds 
the  spark  must  be  advanced  or  made  further 
ahead  of  the  end  of  the  stroke  to  give  the  nec- 
essary time  for  ignition,  while  at  low  speeds  the 
spark  may  be  retarded  or  made  later. 

It  is  necessary  to  provide  high  speed  engines 
with  a  device  for  retarding  the  spark  when  start- 
ting  and  changing  to  the  advanced  position 
after  the  engine  gets  up  speed. 

Owing  to  the  varying  speeds  used  it  is  im- 
possible to  give  a  set  position  for  the  correct 
point  of  ignition,  but  the  proper  timing  of  the 
spark  may  be  readily  determined  by  a  little  ex- 
perimenting with  the  engine  under  full  load. 
The  correct  position  will  soon  be  ascertained 
by  observing  the  results  of  early  or  late  igni- 
tion. 

A  gas  engine  will  run  with  the  valves  and  spark 
considerably  out  of  time,  but  its  full  power  and 
efficiency  will  not  be  developed  unless  the  timing 
is  right. 

Cooling  the  Cylinder.  The  process  of  keep- 
ing the  heat  of  the  walls  and  head  of  the  cylin- 
der down  to  the  proper  temperature  is  called 
cooling  the  cylinder. 

It  is  not  intended  to  make  the  cylinder  cold, 
for  a  cold  cylinder  would  absorb  a  great  amount 
of  the  heat  of  the  explosion.  As  it  is  the  heat 
that  does  the  work  the  object  is  therefore 


166      GAS  AND  OIL  ENGINE  HAND-BOOK 

to  turn  the  greatest  possible  per  cent  of  it  into 
useful  work. 

The  usual  way  of  cooling  the  cylinder  is  to 
circulate  a  quantity  of  water  around  the  cylinder 
and  over  the  head,  through  a  water  jacket.  This 
water  space  is  generally  cast  as  an  integral  part 
of  the  head  and  cylinder. 

The  water  must  be  made  to  circulate  through 
this  space  or  otherwise  it  would  become  very  hot 
and  the  temperature  of  the  cylinder  walls  would 
rise  too  high. 

This  circulation  may  be  obtained  by  a  pump, 
or  by  the  natural  heat  of  the  engine.  If  the 
water  for  cooling  comes  directly  from  a  hydrant 
and  is  allowed  to  waste  after  passing  through 
the  jacket,  care  must  be  taken  to  admit  only 
enough  to  properly  cool  the  engine. 

An  excessive  supply  of  cold  water  pumped 
through  the  jacket  will  produce  bad  results. 

When  natural  circulation  is  used  a  water  tank 
is  used  and  placed  so  that  the  water  level  in  the 
tank  will  be  higher  than  the  engine  cylinder. 
The  tank  is  connected  to  the  water  space  around 
the  cylinder  by  two  pipes,  an  inlet  from  the  bot- 
tom of  the  tank  to  the  lower  part  of  the  jacket 
and  an  outlet  from  the  top  of  the  cylinder  to 
the  upper  part  of  the  tank. 

As  the  water  in  the  jacket  becomes  heated  it 
rises  through  the  outlet  pipe  to  the  top  of  the 
water  level  in  the  tank.  As  the  heat  radiates  or 


GAS  AND  OIL  ENGINE  HAND-BOOK       167 

leaves  the  surface  the  water  becomes  heavier  and 
settles  to  the  bottom  of  the  tank. 

The  same  water  is  thus  used  over  and  over 
again  with  only  a  small  loss  by  evaporation.  The 
size  of  the  tank  must  be  in  proportion  to  the  size 
of  the  engine,  it  must  hold  enough  water  so  that 
the  hot  water,  coming  from  the  engine,will  have 
time  to  cool  before  it  is  needed  again  in  the  jacket. 

Oil,  instead  of  water,  is  being  used  to  a  con- 
siderable extent  by  some  manufacturers.  A 
radiator  or  system  of  pipes  is  used  when  oil  is 
employed  and  the  circulation  through  the  jacket 
is  obtained  similar  to  the  processes  just  described 
for  water,  as  the  general  principles  of  water 
and  oil  cooling  are  the  same.  As  the  oil  will 
not  freeze  and  burst  the  jacket  a  distinct  advan- 
tage over  water  cooling  is  thereby  gained. 

The  next  and  last  means  of  cooling  the  cylin- 
der is  air  cooling. 

The  cylinder  is  made  with  radiating  ribs  or 
fins,  usually  cast  on,  from  which  the  high  heat, 
that  passes  through  the  cylinder  walls,  is  radi- 
ated to  the  surrounding  air. 

This  form  of  cooling  was  first  exploited  in 
small  bicycle  engines  with  cylinders  ranging  from 
2j  to  3j  inches  bore  and  stroke.  Recently  it  is 
being  used  by  automobile  manufacturers  to  cool 
multiple-cylinder  engines. 

Water  Jacket  Temperature.  The  object 
of  the  water-jacket  on  a  gas  engine  cylinder  is 


168       GAS  AND  OIL  ENGINE  HAND-BOOK 

to  maintain  the  cylinder  at  an  even  temperature 
without  over-healing.  If  the  cylinder  were  run 
perfectly  hot,  the  expansion  of  the  metals  would 
be  such  that  the  piston  would  soon  stick,  or 
seize,  and  the.  high  temperature  would  consume 
the  lubricating  oil.  To  get  the  best  results,  the 
temperature  of  the  water  in  the  cylinder  jacket 
should  be  as  near  180  degrees  as  possible,  but 
in  the  marine  motor  little  attention  is  ever  given 
to  this.  As  long  as  the  motor  keeps  reasonably 
cool  and  continues  to  work  well,  the  average 
operator  lets  things  alone.  A  number  of  motors 
have  been  failures  owing  to  insufficient  water- 
jacketing,  and  there  are  others  which  have  had 
too  much  water-jacketing.  The  first  means  that 
the  motors  do  not  work  at  all,  the  latter,  that 
they  do  not  get  the  full  benefit  of  the  expansion 
of  the  gases  and  are  consequently  wasting 
gasoline. 

Pumps.  All  pumps  on  two-cycle  motors  have 
an  impulse  at  every  revolution  of  the  crankshaft. 
This  is  unavoidable,  but  it  is  mechanically  very 
bad  practice,  as  the  average  marine  motor  will 
make  about  500  revolutions  per  minute,  and  any 
plunger  pump  loses  its  efficiency  above  a  speed 
of  300  strokes  per  minute. 

This  is  one  reason  why  in  practice  these 
pumps  give  such  a  poor  circulation.  The  remedy 
would  be  to  gear  the  pump  so  that  the  motor 
would  make  about  four  revolutions  to  one  of  the 


GAS  AND  OIL  ENGINE  HAND-BOOK      169 

pump,  and  increase  the  size  of  the  pump.  This 
would,  however,  add  considerably  to  the  cost  of 
the  engine.  On  some  engines  a  pump  of  the 
rotary  type  is  used,  and  while  these  pumps  will 
deliver  a  perfectly  steady  and  constant  flow  they 
will  soon  lose  their  efficiency  if  there  be  any  sand 
or  grit  in  the  water. 

Vaporizing  Valves.  While  these  valves  are 
exceedingly  simple  and  operated  entirely  by  the 
suction  of  the  engine,  they  are  capable  of  giv- 
ing a  great  deal  of  trouble.  At  the  point  where 
the  gasoline  is  fed  under  the  seat  of  the  valve 
the  opening  is  generally  less  than  one  thirty- 
second  of  an  inch,  and  it  very  often  happens 
that  a  small  particle  of  foreign  substance 
contained  in  the  gasoline  will  settle  at  this 
point. 

When  the  valve  is  pressed  up  by  hand,  the  gaso- 
line will  apparently  flow  all  right,  but  when  the 
engine  is  started  it  will  make  but  a  few  revo- 
lutions and  stop  for  want  of  gasoline.  The 
small  particle,  by  the  quick  suction  of  the  en- 
gine, will  be  drawn  into  the  gasoline  opening, 
shutting  off  the  flow  of  gasoline,  falling  back 
again  when  the  engine  stops,  in  other  words, 
acting  as  a  check  valve.  This  is  a  very  common 
occurrence,  and  a  small  wire  for  cleaning  the 
gasoline  inlet  should  always  be  on  hand.  It 
often  happens  that  the  spring  in  the  vaporizer 
becomes  weak,  and  in  this  case  it  will  admit  of 


170      GAS  AND  OIL  ENGINE  HAND-BOOK 

an  overcharge  of  air.  To  remedy  this,  remove 
the  spring  and  stretch  it  out.  In  order  to  de- 
termine how  much  the  spring  has  been  stretched, 
it  is  a  good  plan  to  measure  it  first. 

Gasoline  Pipes.  A  source  of  trouble  is  in 
the  location  of  the  gasoline  tank.  This  in  many 
cases  has  to  be  placed  so  low  that  if  the  boat  is 
loaded  by  the  head  the  gasoline  will  not  flow  to 
the  vaporizer  when  the  tank  is  nearly  empty. 
A  source  of  annoyance  is  the  practice  of  running 
the  gasoline  pipe  around  under  the  lockers,  es- 
pecially where  the  gasoline  tank  is  low,  as  in 
this  case  the  pressure  of  the  gasoline  in  the  tank 
is  influenced  by  the  rolling  of  the  boat  or  over- 
loading on  either  side.  In  some  cases  the  gaso- 
line is  entirely  shut  off  when  the  boat  is  out  of 
trim.  The  gasoline  pipe  should  in  all  cases  be 
led  down  as  close  to  the  keel  of  the  boat  as 
possible. 

Regrinding  Valves.  The  valves  of  a  gas 
engine  have  to  be  reground  in  case  any  leakage 
occurs,  for,  a  leak  once  started  rapidly  grows 
worse  and  a  serious  leak  makes  starting  diffi- 
cult or  perhaps  impossible.  An  engine  may  run 
along  for  many  months  without  leakage  of 
valves,  but  it  is  good  policy  to  make  occasional 
tests  or  inspection  to  avoid  future  trouble. 

All  valves  made  by  experienced  manufactur- 
ers are  provided  with  a  slot  for  a  screwdriver  as 
a  means  of  rotating  the  valve  on  its  seat. 


GAS  AND  OIL  ENGINE  HAND-BOOK      171 

The  best  material  for  grinding,  tripoli  ground, 
but  as  this  may  be  hard  to  obtain  in  some 
places  flour  of  emery  may  be  substituted.  Flour 
of  emery  may  be  purchased  at  any  drug  store, 
but  it  does  not  grind  so  rapidly  or  make  as 
smooth  a  surface  as  the  tripoli. 

A  little  lard  oil  is  used  to  retain  the  grinding 
material  between  the  valve  and  its  seat.  If  lard 
oil  is  not  at  hand  common  kerosene  will  answer 
the  purpose.  Ordinary  machine  oil  is  a  very 
poor  substitute  and  should  not  be  used  if  lard 
oil  can  possibly  be  obtained. 

Apply  the  oil  and  grinding  material  to  the 
face  of  the  valve  and  replace  in  its  position  in 
the  guide.  With  a  common  bit  brace  and  screw- 
driver blade  revolve  the  valve  on  its  seat  until 
an  even  bearing  is  obtained.  An  ordinary  screw 
will  do  if  the  bit  brace  and  screw-driver  blade 
are  not  available. 

Use  a  firm  steady  pressure  on  the  valve  while 
grinding  but  not  too  much.  Lift  the  valve  from 
its  seat  at  short  intervals  to  allow  the  oil  and 
grinding  material  to  run  back  over  the  surfaces. 
Clean  the  valve  and  seat  occasionally  and  stop  as 
soon  as  a  full  even  bearing  is  shown. 

Restricted  Exhaust  or  Inlet  Ports.  A  re- 
stricted exhaust  may  retain  a  higher  degree  of 
heat  in  the  cylinder  and  thereby  assist  in  main- 
taining incandescent  some  projecting  point  in 
the  combustion  chamber. 


172      GAS  AND  OIL  ENGINE  HAND-BOOK 

Restricted  valve  ports  are  a  hindrance  to 
the  development  of  power.  The  valve  propor- 
tions should  always  be  carefully  figured  from  the 
piston  speed  and  the  cylinder  area. 

The  inlet  valve  area  should  be  such  as  to  give 
the  gases  a  speed  of  from  90  to  100  feet  per  second. 
The  exhaust  gases  should  leave  the  cylinder  at 
from  seventy-five  to  eighty-five  feet  per  second 
at  atmospheric  pressure. 

The  exhaust  valve  should  be  larger  than  the 
inlet  valve,  because  at  the  time  of  opening 
the  exhaust  valve  there  is  a  pressure  of  from 
twenty-five  to  thirty-five  pounds  in  the  cylin- 
der to  relieve,  and  the  velocity  of  the  exhaust 
gases  at  the  moment  of  release  is  above  100  feet 
per  second,  and  if  it  had  to  pass  through  a  re- 
stricted valve  port  it  would  maintain  the  initial 
high  speed  throughout  the  exhaust  stroke  of  the 
piston,  resulting  in  back  pressure  during  the  en. 
tire  exhaust  stroke. 

The  point,  then,  is  to  figure  the  exhaust  port 
of  such  proportions  as  to  relieve  the  exhaust 
gases  at  an  average  speed  throughout  the  ex- 
haust stroke  of  not  over  100  feet  per  second. 

It  is  the  height  of  folly  to  have  a  big  cylinder 
port,  and  then  choke  the  passage  with  a  little 
valve  or  vice  versa. 

The  passage  should  be  of  uniform  area  and 
of  ample  capacity  from  the  cylinder  port  to  the 
end  of  the  pipe. 


GAS  AND  OIL  ENGINE  HAND-BOOK      173 

Types  of  Gasoline  Engines.  When  choos- 
ing a  gasoline  engine  for  operating  a  boat  there 
are  a  number  of  points  to  be  dealt  with.  The 
gasoline  engine  is  expected  to  be  in  working 
order  at  all  times  and  it  must  never  break  down. 
If  it  does,  the  operator  will  decry  the  gasoline  en- 
gine, its  builders  and  all  who  have  anything  to  do 
with  it.  If  a  steam  engine  breaks  down,  there  may 
be  some  strong  words  used  with  reference  to  its 
maker,  but  as  a  rule  nothing  is  said  against  the 
steam  engine  as  a  prime  mover,  for  the  simple 
reason  that  we  are  accustomed  to  its  vagaries."* 

While  much  more  is  expected  of  the  gasoline 
engine  than  of  the  steam  engine,  the  previous 
assertion  is  none  the  less  true  that  reliability  of 
operation  is  the  primary  consideration.  Economy 
of  fuel,  which  is  a  matter  of  first  importance  with 
all  prime  movers  on  land,  becomes  a  secondary 
requirement  as  far  as  the  marine  gasoline  engine 
is  concerned,  and  more  especially  when  these 
engines  are  to  be  used  for  small  powers.  It  is  a 
mistaken  notion  that  anyone  can  operate  a  gaso- 
line engine.  A  child  will  get  on  very  well  after 
being  taught,  and  until  something  happens. 
Then  comes  the  necessity  for  a  man  with  rea- 
soning powers  that  are  well  developed  and  with 
a  clear  head.  All  kinds  of  things  may  happen 
to  a  vessel,  if  its  motive  power  gives  out.  A 
great  many  things  may  happen  to  a  gasoline 
engine  in  indifferent  hands. 


174       GAS  AND  OIL  ENGINE  HAND-BOOK 

Before  going  further  it  may  be  necessary  to 
explain  briefly  the  principles  of  operation  of  the 
two  types  used  for  marine  purposes.  These 
types  are  the  four-cycle  engine,  in  which  there 
is  but  one  impulse  for  each  two  revolutions  of 
the  crankshaft,  and  the  two-cycle  engine,  in 
which  an  impusle  occurs  at  each  revolution  of 
the  crankshaft.  Of  the  two,  the  four-cycle 
engine  is  most  used  for  stationary  purposes,  but 
in  marine  practice  the  two-cycle  engine  is  in  the 
lead.  Although  not  generally  considered  as  eco- 
nomical of  fuel  as  the  four-cycle  engine,  it  can 
be  built  much  lighter  for  the  same  power,  and 
the  great  frequency  of  the  impulses  makes  it 
much  steadier  in  operation.  This  can  perhaps 
be  realized  better  when  it  is  remembered  that 
a  single  cylinder  steam  engine  receives  an  im- 
pulse at  every  stroke  of  the  piston,  or  two  im- 
pulses at  every  revolution  of  the  crankshaft, 
while  the  four-cycle  gasoline  engine  receives  but 
one  impulse  to  two  revolutions,  or  one  impulse 
to  four  in  the  steam  engine.  The  steam  engine 
also  receives  two  impulses  during  the  same  time 
that  the  two-cycle  engine  receives  one. 

Multiple-Cylinder  Engines,  Multiple-cylinder 
engines  of  the  two-cycle  type  have  until  quite 
recently  been  constructed  by  adding  succes- 
sively separate  engines.  While  these  in  a  great 
many  cases  have  given  satisfaction,  they 
have  not  as  a  whole  been  satisfactory.  The 


GAS  AND  OIL  ENGINE  HAND-BOOK      175 

chief  trouble  being  that  when  operated  by  one 
carbureter,  they  have  been  inclined  to  flood  in 
the  after-cylinders.  The  gasoline  gas  being  of 
greater  specific  gravity  than  air,  has  a  tendency 
to  go  to  the  lowest  point,  which  in  the  majority 
of  boats  would  be  the  after-cylinders.  The  dis- 
tance apart  of  the  separate  engines  also  tending 
to  condense  the  vaporized  gasoline,  flooding  the 
crank  bases  of  the  engines  with  the  consequence 
that  no  two  of  the  cylinders  have  a  uniform  mix- 
ture of  gas,  and  in  many  cases  the  after  cylin- 
ders refuse  to  work  at  all.  In  order  to  avoid 
these  difficulties,  many  multiple-cylinder  engines 
have  separate  carbureters  for  each  crank  case. 
While  this  is  all  right  in  theory  it  is  not  good 
practice,  as  it  is  difficult  to  obtain  the  correct 
regulation  of  each  cylinder  when  they  are  all  in 
operation.  There  have  been  placed  on  the  mar- 
ket a  number  of  multiple-cylinder  engines  with 
the  cylinders  in  one  integral  casting  and  sur- 
rounded by  one  water-jacket.  By  this  means 
the  cylinders  are  brought  very  close  together,  us- 
ing one  carbureter,  the  connections  from  it  to 
the  engines  by  this  plan  are  very  short  and 
compact.  These  engines  in  their  very  best  form 
are  not  adapted  to  be  operated  by  a  novice. 
Owing  to  their  high  speed  and  the  number  of 
moving  parts,  it  is  very  difficult  to  detect  and 
locate  troubles  of  any  kind,  and  determine  in 
which  cylinder  the  trouble  exists.  The  four-cycle 


176      GAS  AND  OIL  ENGINE  HAND-BOOK 

multiple-cylinder  engine  is  an  entirely  differ- 
ent proposition,  and  especially,  the  double  cylin- 
der, which  is  very  successful.  The  two-cylinder 
four-cycle  engine  produces  the  same  results  and 
only  has  the  same  number  of  movements  as  in 
the  single-cylinder  two-cycle,  therefore  a  four- 
cycle four-cylinder  is  equivalent  to  a  two-cylin- 
der two-cycle  engine.  One  of  the  principal 
troubles  of  the  multiple-cylinder  high  speed 
engine  is  the  ignition,  as  they  are  very  hard  on 
generators  and  batteries. 

Selecting  a  Boat  Engine.  The  thing  for 
the  prospective  purchaser  to  do  is  naturally 
to  write  to  different  makers  of  gasoline  engines 
and  obtain  their  catalogues  and  price  lists.  It 
will  be  found  that  each  one  is  building  the  best 
engine  on  earth,  if  his  story  is  to  be  believed. 
It  is  a  sad  truth,  indeed,  that  there  are  many 
poor  gasoline  engines  offered  for  sale  in  the  open 
market.  Several  catalogues  will  probably  con- 
tain an  engine  very  nearly  the  size  which  has 
been  selected  for  the  new  boat.  If  the  catalogues 
received  contain  testimonials  from  persons  who 
live  in  the  vicinity,  make  it  a  point  to  call  on 
them,  and  have  a  private  talk  with  them  about 
their  engines. 

Find  out  how  much  the  engine  has  been  run, 
and  obtain  a  narrative  of  all  experiences  with 
the  engine  when  running.  Find  out  the  longest 
as  well  as  the  shortest  period  of  time  it  has  taken  to 


GAS  AND  OIL  ENGINE  HAND-BOOK       177 

get  the  engine  started,  and  how  long  it  has  been  run 
at  any  one  time  without  stopping.  Find  out  if 
the  engine  is  addicted  to  thumping  or  pounding 
in  any  part  of  the  mechanism,  and  whether  such 


FIG  44 

Single-cylinder,  two-cycle  Marine  Motor. 

a  condition  is  of  frequent  occurrence,  or  only  oc- 
casional, and  also  how  long  the  ignition  appa- 
ratus will  last.  If  it  be  found  that  the  engine 
transmits  very  little  vibration  to  the  boat,  it  may 
be  presumed  that  the  engine  is  well  balanced. 


178      GAS  AND  OIL  ENGINE  HAND-BOOK 

Another  way  to  tell  whether  an  engine  is  in 
good  balance  is  to  see  if  it  will  run  for  quite  a 
little  time  after  the  ignition  current  has  been  cut  off. 
Of  two  engines,  that  are  of  the  same  size,  and 
equally  well  lubricated,  and  which  have  the  same 
friction  resistance,  the  engine  will  run  the  longer 
after  power  is  shut  off  that  is  the  better  bal- 
anced. When  resting  the  hand  upon  the  cylin- 
der head  while  the  engine  is  running  idle,  if  a 
knock  is  perceptible  it  is  a  certain  sign  that  it  is 
out  of  balance. 

If  the  engine  is  counterbalanced  in  the  fly- 
wheel instead  of  on  the  crank  jaws  it  gives  a 
twisting  movement  to  the  shaft,  and  the  balanc- 
ing is  imperfect.  A  well-balanced  engine  should 
have  the  counter-weight  as  nearly  opposite  the 
the  crank  pin  as  it  is  possible  to  place  it.  In 
a  two-cylinder  engine  with  the  crank  pins  at  180 
degrees,  or  in  a  three-cylinder  engine  with  the 
cranks  at  120  degrees,  a  balancing  effect  is  ob- 
tained which  is  much  better  than  that  produced 
by  a  counter-weight.  It  is  the  custom  with 
some  builders  to  put  the  crank  pins  on  the  same 
side  of  the  shaft  for  a  two-cylinder  engine,  for 
the  reason  that  the  impulses  are  better  distributed. 
It  is  generally  admitted  that  a  better  mechan- 
ical balance  is  obtained  with  the  crank  pins 
at  180  degrees  and  in  a  vertical  two-cylinder 
engine  of  the  four-cycle  type  with  an  enclosed 
crank  case,  the  latter  arrangement  avoids  the 


r 
GAS  AND  OIL  ENGINE  HAND-BOOK       179 

pumping  action  that  occurs  when  the  cranks  are 
on  the  same  side  of  the  shaft. 

If  the  counter-weight  be  in  the  flywheel,  see 
if  it  has  any  side  motion  when  the  engine  is  run- 
ning, or,  in  other  words,  see  if  the  flywheel  is 
out  of  true  sideways.  If  such  is  the  case,  it 
shows  that  the  crank  shaft  is  too  weak  for  an 
engine  of  this  kind. 

Find  out  if  the  bearings  give  trouble  from  over 
heating,  and  be  particular  to  ask  for  any  ex- 
perience in  this  matter.  Find  out  if  it  is  nec- 
essary to  watch  the  engine  at  all  times,  or 
whether  you  may  be  secure  in  giving  the 
engine  only  an  occasional  glance  to  see  if  it 
is  running  all  right. 

Handling  Marine  Engine  with  Reverse 
Lever.  In  handling  the  engine  when  desiring  to 
make  a  stop,  no  matter  whether  equipped  with 
reversing  gear  or  reversing  propeller,  never  stop 
the  engine  until  the  actual  stopping  point  is 
reached.  Many  accidents  are  caused  by  opera- 
tors getting  excited  and  stopping  the  motor  when 
it  should  have  been  allowed  to  run  and  depend 
on  the  reversing  mechanism.  When  the  engine 
has  no  reversing  device  and  is  dependent  upon 
reversing  the  engine,  always  make  the  approach 
to  a  landing  from  the  side. 

Propellers  for  Motor  Boats.  The  propel- 
ler wheels  used  on  motor  boats  are,  as  a  rule, 
smaller  in  diameter  than  employed  in  steam 


180      GAS  AND  OIL  ENGINE  HAND-BOOK 

practice,  the  reason  for  this  being  that  the  gaso- 
line engine  is  usually  run  at  a  higher  rate  of 
speed,  and  where  no  reversing  gear  is  used,  the 
engine  has  to  start  against  the  full  load  of  the 


FIG.  45 

Two-cylinder,  two-cycle  Marine  Motor. 

wheel.  Of  late,  the  manufacturers  have  been 
using  wheels  of  larger  diameter  and  less  pitch, 
the  effect  of  this  being  to  increase  the  efficiency 
of  the  propeller,  making  the  engine  easier  to 
start,  decreasing  the  number  of  revolutions  some- 


GAS  AND  OIL  ENGINE  HAND-BOOK       181 

what,  but  adding  to  the  speed  of  the  boat.  In 
order  to  avoid  the  use  of  the  reversing  gears  in- 
side the  boat,  the  reversing  propeller  is  used  to 
a  large  extent.  These  wheels,  although  of  many 
different  patterns,  are  all  practically  of  the  same 
principle,  the  blades  being  turned  by  the  move- 
ment of  a  sleeve  surrounding  the  propeller  shaft, 
which  revolves  with  the  shaft.  There  are  no  gears 
to  intermesh  or  any  necessity  for  slowing  down 
as  with  the  inside  reversing  mechanism.  These 
propellers  will  reverse  at  full  speed  as  they  al- 
ways travel  in  the  same  direction,  they  take  hold 
of  the  water  instantly. 

The  reversing  propeller  is  necessarily  some- 
what weak  structurally.  It  being  impossible, 
for  mechanical  reasons,  to  design  it  as  a  per- 
fectly true  screw.  It  therefore  lacks  the  effi- 
ciency of  a  solid  propeller. 

The  word  pitch,  as  applied  to  the  propeller 
wheel,  refers  to  it  in  the  same  sense  as  to  the 
pitch  of  a  screw,  as  the  propeller  in  action  should 
be  a  perfect  screw.  The  pitch  of  the  propeller 
designates  the  number  of  feet  that  it  would 
travel  in  one  revolution,  supposing  it  to  be  a 
screw.  If  a  propeller  wheel  is  20  inches  in  diam- 
eter and  has  30  inches  pitch,  it  denotes  that  it 
will  travel  30  inches  in  each  revolution.  It  is  by 
this  means  that  calculations  are  made  on  the 
speed  of  the  boat.  In  small  motor  boats  any  esti- 
mates based  on  these  calculations  will,  as  a  rule, 


182       GAS  AND  OIL  ENGINE  HAND-BOOK 

prove  anything  but  reliable,  as  the  proportion 
of  beam  to  length  is  in  all  cases  excessive  in 
comparison  with  larger  vessels.  Of  course,  as 
the  pitch  of  the  propeller  wheel  is  decreased,  a 
slower  screw  is  had  and  consequently  a  more 
powerful  one.  For  this  reason  it  is  becoming 
the  practice  of  high  speed  boats  to  use  a  wheel 
of  the  least  possible  pitch,  and  in  order  to  gain 
on  the  travel  of  the  screw  to  increase  the  num- 
ber of  the  revolutions  of  the  propeller. 

The  form  and  general  design  of  the  propeller 
have  been  so  extensively  experimented  with, 
that  the  subject  is  almost  worn  threadbare,  and 
it  is  sufficient  to  say  that  the  true  screw  propel- 
ler will,  in  all  probability,  remain  as  at  first  the 
standard  of  excellence. 

Couplings  and  Thrust  Bearings.  On  the 
opposite  end  of  the  crank  shaft  from  the  fly- 
wheel, is  the  shaft  coupling  and  thrust  bearing. 
The  thrust  bearing,  which  is  intended  to  take 
up  the  thrust  or  push  from  the  propeller,  is 
sometimes  made  up  of  a  number  of  balls  fitted 
in  a  cage  between  the  couplings  and  the  after 
bearing  of  the  engine,  or  in  a  great  many  cases 
a  groove  is  turned  in  the  coupling  for  a  ball  race, 
the  oposite  side  being  a  flat,  hardened  steel 
washer.  While  this  is  a  very  neat  and  effect- 
ive arrangement,  it  has  been  found  from  actual 
experience  that  ball-bearings  in  marine  work  are 
not  a  success.  The  older  method,  and  the  one 


GAS  AND  OIL  ENGINE  HAND-BOOK      183 

still  used  on  large  marine  engines,  is  the  ring 
thrust,  composed  of  a  shaft  with  a  number  of 
collars  turned  on  it  which  mesh  into  a  set  of 
babbitt  metal  rings  fastened  to  the  keel  and 
entirely  separate  from  the  engine.  The  neces- 
sity of  a  good  thrust  bearing,  is  sadly  neglected 
by  the  launch  owner,  as  a  thrust  bearing  of 
good  design,  if  carefully  looked  after,  will  in  the 
majority  of  cases  not  only  keep  the  engine  in 
much  better  working  order  and  save  a  good  deal 
of  wear,  but  in  many  cases  prevent  a  broken 
connecting  rod. 

Gas  Engine  Design.  The  builders  of  gas 
engines  have  brought  out  a  great  number  of  dif- 
ferent designs  in  construction. 

Out  of  all  this  there  have  been  evolved  certain 
constructions  that  have  come  to  be  recognized 
as  standard  and  followed  by  most  builders. 

Cylinders  are  built  in  either  a  vertical  or  hori- 
zontal position. 

The  principal  claims  for  the  vertical  con- 
struction are: 

Minimum  floor  space  occupied,  impulses  de- 
livered in  the  line  of  the  foundation,  thus  les- 
sening the  vibration.  Less  wear  on  the  piston 
and  cylinder  by  supporting  the  weight  of  the 
piston  on  the  connecting  rod  instead  of  allow- 
ing it  to  lie  on  one  side  in  the  cylinder. 

These  advantages  are  met  by  claims  for  a 
horizontal  construction  in  that  better  lubrica- 


184      GAS  AND  OIL  ENGINE  HAND-BOOK 

tion  of  the  piston  and  cylinder  walls  is  obtained 
by  feeding  the  oil  on  top  of  the  piston,  so  that 
it  will  flow  by  gravity  to  all  parts  of  the  wear- 
ing surface. 

As  both  constructions  are  in  demand  and  both 
give  excellent  results  in  practical  use,  it  becomes 
a  matter  of  taste  with  the  purchaser,  and  many 
manufacturers  settle  the  question  by  building 
both  the  vertical  and  horizontal  types. 

In  most  gas  engines  the  connecting  rod  is 
attached  directly  to  the  piston  thus  eliminating 
the  heavy  crosshead  and  piston  rod  peculiar  to 
the  steam  engine.  As  the  mass  or  weight  of 
reciprocating  parts  is  thus  greatly  reduced  the 
gas  engine  thereby  approaches  the  ideal  engine. 

A  point  in  late  design  is  the  tendency  to  mul- 
tiple-cylinder construction,  using  two,  three,  four 
and  sometimes  six  cylinders.  Such  construc- 
tions are  much  more  expensive  to  build,  but  the 
important  advantages  of  less  weight  for  a  given 
power,  constant  torque  or  turning  movement,  less 
vibration  due  to  better  balance  and  the  increased 
chances  against  complete  disability  are  bringing 
multiple-cylinder  engines  into  general  favor. 

In  an  engine  with  two  or  more  cylinders  the 
principle  of  operation  for  each  cylinder  is  the 
same  as  for  a  single-cylinder  engine.  The  cylin- 
ders are,  however,  made  to  deliver  their  impulses 
one  after  the  other,  the  time  between  the  im- 
pulses being  made  as  nearly  equal  as  possible. 


GAS  AND  OIL  ENGINE  HAND-BOOK       185 

Fore-Sight  Visible  Spark  Plug.  The  great 
utility  of  this  improved  electric  sparking  device 
for  gas  engines  has  been  established  by  thorough 
working  tests  under  the  most  severe  conditions. 
It  is  especially  designed  for  use  with  gas 
engines  operating  motor  vehicles.  This  type  of 
engine  requires  a  perfect  sparking  action  to 
meet  the  exacting  requirements  of  modern  serv- 
ice, and  must  be  entirely  dependable  under 
the  most  trying  and  adverse  circumstances. 

The  vital  working  parts  of  a  motor  vehicle 
must  be  perfectly  protected  against  fouling,  and 
at  the  same  time  should  be  quickly  accessible 
for  thorough  inspection.  Ease  of  operation, 
personal  comfort,  and  safety  must  be  assured 
by  every  successful  motor. 

The  Fore-Sight  Visible  Spark  Plug  is  con- 
structed on  the  principle  of  reduced  voltage. 
An  electric  current  of  low  voltage  will  arc  or 
spark  instead  of  following  a  path  of  high  re- 
sistance formed  by  carbon  or  other  deposits. 
A  low  voltage  is  obtained  in  this  plug  without 
reduced  amperage. 

An  auxiliary  sparking  gap  co-operating  with 
.the  main  ignition  gap  is  so  placed  as  to  be  vis- 
ible to  the  eye  and  admitting  of  easy  inspection 
at  all  times.  The  working  condition  of  the  spark 
is  thus  plainly  discernible  without  the  removal 
of  the  plug  from  the  cylinder.  This  is  a  great 
saving  of  time  as  it  aids  the  operator  in  locating 


186      GAS  AND  OIL  ENGINE  HAND-BOOK 


the  cause  of  trouble  and  prevents  useless  inspec- 
tion of  parts  not  affected. 

Road  de- 
lays are  an- 
noying at  all 
times  and  es- 
pecially so  in 
emergencies. 

Begrimed 
hands,   soiled 
clothing    and 
a       damaged 
temper   could 
be  averted   if 
the         driver 
knew     the 
s  park   was 
right  without  wasting 
his  time  in  its  inspec- 
tion.   The  Fore-Sight 
Visible     Spark    Plug, 
Figure    46,  shows  its 
condition  instantly. 

It  is  accurate,  re- 
liable, durable,  and 
should  be  in  use  on 
every  motor  where 
time,  safety  and  speed 
F|G  47  are  required. 

outside  view  of  Fore-Sight  The  Foresight  Vis- 

Visible  Spark  Plug. 


FIG.  46 

The  Fore-Sight  Visible  Spark  Plug  Showing 

Auxiliary  Sparking  Gap  and  Main 

Multi-Point    Ignition  Gap. 


GAS  AND  OIL  ENGINE  HAND-BOOK       187 


ible  Spark  Plug  is  constructed  only  of  the  very  best 
material.  Its  parts  are  simple  and  accurately  fit- 
ted by  skilled  mechanics. 
It  is  absolutely  closed  to 
dirt  or  water  and  works 
perfectly  under  condi- 
tions that  would  put  the 
ordinary  plug  out  of 
business.  It  will  run 
longer  without  exhaus- 
tion than  any  other  plug 
on  the  market.  It  never 
misses  a  spark  and  is  in- 
stantly visible  to  the  eye 

t  *u     A  •         u       •       i  F|G-  48 

of  the  driver  by  simply  Sectional  View  of  Fore_Sight 

raising    the    hood.      See          Visible  s?ark  P1"g 
Figures  47  and  48.  EXPLANATION 

a— Cylinder  Wall. 
Its    Sparking    Center   IS  6— Hollow  Plug.     Engaged  into 

interchangeable    and  can  ^ignition  points. 

be  renewed    at     any  time  c— Tubular  socket  engaged  into 
at  the  COSt    of  a  few  Cents.  C2-Sight  opening  to  sparking 

Figure    49    shows  our  ^api ,  " 

a— Platinum   point  in  ignition 

Multi-Point  spark   plug.  gap. 

T.   .  j    .        r  .1       d%— Platinum  point  in  auxiliary 

It  is  turned  to  show  the  gap 

Multi-Point  sparkinggap.  <*3-Terminal  member. 

d4-5-6— Washers. 
It  IS  made  of  the  same  d7— Nut  adjusting  circuit  wire 

fine   material   and    good  *?;i™Sating  bushings. 

Workmanship,      and      ex-  {/—Glass  or    transparent    mica 

tube. 


cepting       the      secondary  ft-Binding  post  connecting  cir- 

spark  is  ide 

Fore-Sight. 


spark  is  identical  with  the  ?uit  wire* 


Open  space  to  prevent   car- 
bonization. 


188      GAS  AND  OIL  ENGINE  HAND-BOOK 

This  Plug  is  far  superior  to  any  closed  plug 
on  the  market. 

It  is  of  bet- 
ter material 
and  w  o  r  k- 
manship. 

It  is  fitted 
with  a  deeply 
milled  set 
screw  for  cir- 
cuit wire  at 
top,  easily 
turned  with 

Multi-Point  Spark  Plug  Showing  Multi-Point  nn£ers»    Wlth- 
Sparking  Points  OUt  pliers. 

It  is   absolutely  dirt  and  water  proof  and  per- 
fectly insulated. 

Its  platinum  pins  last  longer  than  in  any  other 
plug. 

Its  Multi-Points  absolutely  guarantee  a  spark, 
a  positive  spark  that  will  not 
stop  until  the  driver  wills  it. 
It  is  safe,  reliable  econom- 
ical, and   costs  no  more  than 
a  single  point    plug  that  soon 
becomes  foul    and  worthless. 
FIG.  50  Figure  50  shows  an  enlarged 

end  view  of  the  Ignition  Gap  of  our  Fore- 
Sight  and  Multi-Point  spark  plugs.  Note  the 
several  spark  points. 


GAS  AND  OIL  ENGINE  HAND-BOOK      189 

This  very  important  feature  merits  the  special 
attention  of  every  owner  and  operator  of  a  Motor. 
It  is  the  heart  of  the  vehicle  and  its  life  spark 
must  be  positive  and  constant. 

A  great  percentage  of  road  delays  is  caused  by 
"heart  failure."  Most  plugs  in  use  are  of  single 
point  ignition  and,  being  easily  fouled  by  corro- 
sion, a  short  circuit  and  consequent  stop  is 
inevitable. 

With  our  Multi-Point  sparking  gap,  ignition 
is  constant  and  sure.  There  is  no  corrosion  of 
the  platinum  pin  and  the  points  being  thin,  the 
temperature  rises  just  high  enough  to  vaporate 
the  oil,  instead  of  forming  obstructive  carbon 
deposits. 

The  Multi-Point  sparking  center  is  interchange- 
able in  the  Fore-Sight  Visible  Spark  and  is  the 
only  interchangeable  spark  center  that  can  be  so 
cheaply  renewed. 


INDEX 


Page 

Actual  horsepower 7 

Anti-freezing  solutions 7 

Backfiring 8 

Bearings 8 

Bearings,  Heated 10 

Calorific  values  of  fuels  10 

Cams 11 

Cam  shaft  gearing 12 

Carbureter,  Use  of 14 

Care  of  gas  or  oil  engines 16 

Cleaning  a  gas  or  oil  engine 17 

Combustion  chamber,  Design  of . .  18 
Combustion  chamber,  Dimensions 

of 18 

Comparison  of  gas  and  steam  en- 
gines    20 

Comparison  of  horizontal  and  ver- 
tical engines 21 

Comparison  of  two  and  four-cycle 

engines 22 

Compressed  air  starters 23 

Compression,  Advantages  of 25 

Compression,  How  to  calculate  . .  25 

Compression,  Leaks  in 27 

Compression,  Loss  of 28 

Connecting  rods 29 

Cooling  the  cylinder 165 

Couplings  and  thrust  bearings. . .  182 

Cycles  of  gas  and  oil  engines 30 

Cylinders,  Construction  of 32 

Cylinder,  Method  of  boring 33 

Cylinder  sweating 34 

Design  of  gas  and  oil  engines 34 

Deep  well  pumping  plants 35 

Dry  batteries 35 

Dynamometer 37 


Electricity,  Forms  of 39 

Electric  light  outfits 39 

Exhaust,  Cause  of  smoky 42 

Explosions  in  the  inlet-pipe 42 

Explosions,  Weak 43 

Fire  insurance 43 

Fire  pot  or  muffler 43 

Flash  tests  of  oils 45 

Flywheels 46 

Foundation  bolts 47 

Foundations 48 

Four-cycle  engine,  Construction  of  48 

Four-cycle  engine,  Operation  of . .  49 

Four-cycle  engine,  Principle  of . . .  51 

Four-cycle  marine  engines 53 

Friction  clutches 53 

Fuel  consumption  of  gas  and  oil 

engines 55 

Fuel  gas  oil 56 

Gas  engine  design 183 

Gas  engine  troubles 159 

Gases,  Expansion  of 57 

Gasoline,  How  obtained 57 

Gasoline  or  kerosene  fires 58 

Gasoline  pipes 170 

Gasoline  pump 59 

Gasoline  traction  engines 60 

Gas  or  oil  engines,  Successful  op- 
eration of 61 

Generator 62 

Governing  gas  or  oil  engines 62 

Handling  marine  engine  with  re- 
verse lever 179 

Hand  starting  device 66 

Horsepower  of  gas  or  oil  engines.  66 

Hot  tube  ignition 69 


Efficiency,  Mechanical    37        Igniter,  Cleaning  an 70 

Efficiency,  Thermal 38       Ignitior,  Catalytic 70 

190 


INDEX 


191 


Page 

Ignition,  Forms  of 70 

Ignition  mechanism 72 

Ignition,   Reason  for  advancing 

point  of 73 

Indicator  diagrams 73 

Indicator,  Use  of  the 76 

Inspecting  gas  or  oil  engines 77 

Installing  a  gas  or  oil  engine 77 

Jump-spark  wiring  diagram 79 

Knocking  or  pounding  in  an  engine  79 

Liquid  fuels 82 

Locating  an  engine 83 

Lubricants 84 

Lubrication  of  oil  engine  cylinders  8  6 

Lubricators 87 

Magneto  generator 87 

Misfiring,  Causes  of 88 

Mixing  valve 89 

Multiple-cylinder  engines 174 

Oil  engine  cycle 90 

Oiling  a  gas  engine 160 

Oil  vaporization,  Methods  of 91 

Oil  vaporizer,  Crude 92 

Oil  vaporizers 93 

Overheating,  Causes  of 94 

Pistons 95 

Piston  displacement 96 

Pistons,  Length  of 96 

Piston-rings 97 

Piston-rings,  Method  of  turning. .  97 

Piston  velocity 99 

Portable  oil  engines 101 

Pumps 168 

Premature  ignition,  Causes  of 103 

Primary  spark  coil 103 

Primary  spark  plug 104 

Prony  brake 105 

Propellers  for  motor  boats 179 

Regrinding  valves 169 

Repairing  a  gas  or  oil  engine 107 


Page 
Restricted  exhaust  or  inlet  ports.  171 

Secondary  coil 108 

Selecting  a  boat  engine 176 

Smoke  from  cylinder,  Cause  of . . .  110 

Solders  and  spelters 110 

Spark  plug 185 

Starting  a  gas  engine 110 

Starting  a  gasoline  engine Ill 

Starting  a  gasoline  or  kerosene  en- 
gine for  the  first  time 112 

Starting  a  gas  or  oil  engine,  Gen- 
eral directions  for 112 

Starting  a  kerosene  engine 114 

Starting  oil  engines,  New  method 

of 115 

Starting  troubles 116 

Stopping  a  gas  or  oil  engine 117 

Stopping  troubles 118 

Tachometer 118 

Tanks,  Capacity  of  cylindrical  ...  118 

Tanks,  Installation  of  gasoline. . .  118 

Throttle,  Use  of 120 

Timing  the  spark 164 

Two-cycle  engine,  Construction  of  120 

Two-cycle  engine,  Principle  of . . .  122 

Two-cycle  marine  engine 123 

Types  gasoline  engines 173 

Valves 124 

Valves  and  valve  chambers 125 

Valves,  Diameter  and  lift  of 126 

Valve  "lifters  128 

Valve  operating  mechanism 128 

Valve  stems,  Fit  of 129 

Valves,  Timing  of 129 

Vaporizing  valves 169 

Viscosity  of  oils 131 

Water  cooling  system 131 

Water-jackets 133 

Water-jacket  circulation 134 

Water-jacket,  Draining  the 135 

Water-jacket  temperature 167 

Water-jacket,  Testing  of 135 


192 


INDEX 


TABLES 


Density  and  specific  gravity  equiv- 
alents    136 

Dimensions  of  machine  screws. . .  137 
Safe  working  load  of  steel  balls. .  137 

Composition  of  alloys 137 

Strength  and  weight  of  materials  138 
Dimensions  of  involute  tooth  spur 

gears 138 

Melting  point  of  metals 139 

Weight  per  cubic  foot  of  sub- 


Wrought  iron  pipe,  Dimensions  of  140 

Properties  of  compressed  air 141 

Decimals  of  an  inch 141 

Weight  of  square  head  machine 

bolts 142 

Weight  of  nuta  and  bolt  heads  . .  142 


Page 

Copper  wire  gauge  table 143 

Squares  and  square  roots  of  num- 
bers   144 

Areas     and     circumferences     of 

circles 145 

Dimensions  of  cap  screws 147 

Dimensions  of  tap  drills 147 

Calorific  power  of  various  fuels. .  148 
Weight  per  cubic  foot  of  gases. .  148 

Heat  values  of  fuels. T 149 

Areas   of  circles   from  0.001    to 

100.9 150 

Dimensions    of   U.    S.    Standard 

Threads 155 

Circumferences    of    circles    from 

0.01  to  80.9 156 

Mensuration  of  surface  and  volume  157 


THE  AUTOMOBILE  HAND-BOOK 


A  WORK  of  practical  information  for  the  use  of  Owners,  Operators  and 
•*"*•  Automobile  Mechanics,  giving  full  and  concise  information  on  all 
questions  relating  to  the  construction,  care  and  operation  of  gasoline  and 
electric  automobiles,  including  Road  Troubles,  Motor  Troubles,  Carbu- 
reter Troubles,  Ignition  Troubles,  Battery 
Troubles,  Clutch  Troubles,  Starting 
Troubles.  Pocket  size,  4x6^.  Over  200 
pages.  With  numerous  tables,  useful 
rules  and  formulas,  wiring  diagrams  and 
over  100  illustrations,  by 

L.  ELLIOTT  BROOKES 

Author  of  the  "Construction  of  a  Gasoline  Motor." 


This  work  has  been  written  especially 
for  the  practical  information  of  automo- 
bile owners,  operators  and  automobile 
mechanics.  Questions  will  arise,  which 
are  answered  or  explained  in  technical 
books  or  trade  journals,  but  such  works 
are  not  always  at  hand,  or  the  information 
given  in  them  not  directly  applicable  to  the 
case  in  hand. 

In  presenting  this  work  to  readers  who  may  be  interested  in  automo- 
biles, it  has  been  the  aim  to  treat  the  subject-matter  therein  in  as  simple 
and  non-technical  a  manner  as  possible,  and  yet  to  give  the  principles, 
construction  and  operation  of  the  different  devices  described,  briefly  and 
explicitly,  and  to  illustrate  them  by  showing  constructions  and  methods 
used  on  modern  types  of  American  and  European  cars. 

The  perusal  of  this  work  for  a  few  minutes  when  troubles  occur,  will 
often  not  only  save  time,  money  and  worry,  but  give  greater  confidence  in 
the  car,  with  regard  to  its  going  qualities  on  the  road,  when  properly  and 
intelligently  cared  for.  ^ 

In  conclusion  it  may  be  stated  that  at  the  present  time  nearly  all  auto- 
mobile troubles  or  breakdowns  may,  in  almost  every  case,  be  traced  to 
the  lack  of  knowledge  or  carelessness  of  the  owner  or  operator  of  the  car. 
rather  than  to  the  car  itself.  16mo.  320  pages,  and  over  100  illustrations. 

Popular  Edition,  Full  Leather  Limp.     Price  net $1.5O 

Edition  de  Luxe,  Full  Red  Morocco,  Gold  Edges.    Price  net. .   2.00 

~~  Sent  Postpaid  to  any  Address  in  the  World  upon  Receipt  of  Price 

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350-352  Vaiash  Avenue,  CHICAGO,  ILL. 


THE  MOST  IMPORTANT  BOOK  ON  ELECTRICAL  CONSTRUCTION 

WORK   FOR   ELECTRICAL   WORKERS    EVER  PUBLISHED. 

NEW  19O4   EDITION. 

MODERN    WIRING 
DIAGRAMS  AND  DESCRIPTIONS 

A  Hand  Book  of  practical  diagrams  and 
information  for  Electrical  Workers. 

By  HENRY  C.  HORSTMANN  and 
VICTOR  H.  TOUSLEY 
Expert  Electricians. 

This  grand  little  volume  not  only  tells 
you  how  to  do  it,  but  It  shows  you. 

The  book  contains  no  pictures  of 
bells,  batteries  or  other  fittings ;  you  can 
see  those  anywhere. 

It  contains  no  Fire  Underwriters- 
rules;  you  can  get  those  free  anywhere. 
It  contains  no  elementary  considera- 
tions; you  are  supposed  to  know  what 
an  ampere,  a  volt  or  a  "short  circuit" 
is.   And  it  contains  no  historical  matter. 
All  of  these  have  been  omitted  to 
make   room  for   "diagrams   and  de- 
scriptions" of  just  such  a  character  as 
workers  need.     We  claim  to  give  all 
that  ordinary  electrical  workers  need 
and  nothing  that  they  do  not  need. 
It  shows  you  how  to  wire  for  call  and  alarm  bells. 
For  burglar  and  fire  alarm. 
How  to  run  bells  from  dynamo  current, 
How  to  install  and  manage  batteries. 
How  to  test  batteries. 
How  to  test  circuits. 

How  to  wire  for  annunciators;  for  telegraph  and  gas  lighting. 
It  tells  how  to  locate  "trouble"  and  "ring  out"  circuits. 
It  tells  about  meters  and  transformers. 
It  contains  30  diagrams  of  electric  lighting  circuits  alone. 
It  explains  dynamos  and  motors;  alternating  and  direct  current. 
It  gives  ten  diagrams  of  ground  detectors  alone. 
It  gives  "Compensator"  and  storage  battery  installation. 
It  gives  simple  and  explicit  explanation  of  the  "  Wheatstone"  Bridge 
and  its  uses  as  well  as  volt-meter  and  other  testing. 

It  gives  a  new  and  simple  wiring  table  covering  all  voltages  and  all 
losses  or  distances. 

Ifimo.,  160  pages,  200  illustrations;  full  leather  binding, 
round  corners,  red  edges.    Size  4x6,  pocket  edition.    PRICE 

Sold  by  booksellers  generally  or  sent  postpaid  to  any  address 
upon  receipt  of  price. 

FREDERICK  J.  DRAKE  &  CO.,  Publishers 

350-352  Vabash  Avenue,  CHICAGO,  ILL. 


MODERN  ELECTRICAL 
CONSTRUCTION 


By  HORSTMANN  and  TOUSLEY 


TjfHIS   book  treats  almost  entirely   of    practical    electrical 

^^    work.     It  uses  the  '  'Rules  and  Requirements  of  the  Na- 

tional Board  of  Fire  Underwriters"  as  a  text,  and  ex- 

plains by  numerous  cuts  and  detailed  explanations  just  how 

the  best  class  of  electrical 
work  is  installed. 

It  is  a  perfect  guide  for 
the  beginning  electrician 
and  gives  him  all  the 
theory  needed  in  practical 
work  in  addition  to  full 
practical  instructions.  For 
the  journeyman  electrician 
it  is  no  less  valuable,  be- 
cause it  elaborates  and 
explains  safety  rules  in 
vogue  throughout  the 
United  States.  It  is  also 
of  especial  value  to  elec- 
trical inspectors,  as  it 
points  out  many  of  the 
tricks  practiced  by  un- 
scrupulous persons  in  the 
trade. 

The  book  also  contains  a 
number  of  tables  giving  di- 
mensions and  trade  num- 
bers of  screws,  nails,  in- 
sulators and  other  material 
in  general  use,  which  will  be  found  of  great  value  in  practice. 
There  is  also  given  a  method  by  which  the  diameter  of  con- 
duit necessary  for  any  number  of  wires  of  any  size  can  be  at 
•  once  determined.  The  motto  of  the  authors,  "To  omit  noth- 
ing that  is  needed  and  include  nothing  that  is  not  needed  "/' 
that  has  made  "Wiring  diagrams  and  Descriptions"  so  suc- 
cessful, has  been  followed  in  this  work.  No  book  of  greater 
value  to  the  man  who  does  the  work  has  ever  been  published. 
16mo,  250  pages,  100  diagrams.  Full  leather,  limp. 

=    Price,    net,    $1.SO  • 

Sent  postpaid  to  any  address  in  the  world  upon  receipt  of  price 

FREDERICK  J.  DRAKE  &  CO. 

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MODERN  LOCOMOTIVE 
ENGINEERING 


20th  CENTURY 
EDITION 


By  C.  F.  SWINGLE,  M.  E, 


THE  most  modern  and  practical  work  published,  treating  upon  the 
construction  and  management  of  modern  locomotives,  both  simple 
and  compound. 

The  aim  of  the  author  in  compiling  this  work  was  to  furnish  to  loco- 
motive engineers  and  firemen,  in  a  clear  and  concise  manner,  such  in- 
formation as  will  thoroughly  equip  them  for  the  responsibilities  of  their 
calling.  The  subject-matter  is  arranged  in  such  a  manner  that  the  fire- 
man just  entering  upon  his  apprenticeship  may,  by  beginning  with  chapter 
I,  learn  of  his  duties  as  a  fireman  and  then,  by  closely  following  the  make- 
up of  the  book  in  the  succeeding  pages,  will  be  able  to  gain  a  thorough 
knowledge  of  the  construction,  maintenance  and  operation  of  all  types  of 
engines. 

Breakdown,  and  what  to  do  in  cases  of  emergency,  are  given  a  con- 
spicuous place  in  the  book,  including  engine  running  and  all  its  varied 
details.  Particular  attention  is  also  paid  to  the  air  brake,  including  all 
new  and  improved  devices  for  the  safe  handling  of  trains. 

The  book  contains  over  600  pages  and  is  beautifully  illustrated  with 
line  drawings  and  half-tone  engravings.  Plain,  simple  and  explicit  lan- 
guage is  used  throughout  the  book,  making  it  unquestionably  the  most 
modern  treatise  on  this  subject  in  print, 

Size  5x6%.  Pocket-book  style.  Full  seal  grain  leather,  with  gold 
stampings  and  gold  edges.  Price,  $3.0O 

Sent  Postpaid  to  any  Address  in  the  World  upon  Receipt  of  Price 

FREDERICK  J.  DRAKE  &  CO. 

PUBLISHERS 


350-352  Wabash  Avenue,  CHICAGO,  ILL. 


This  new  1905  Edition  contains  in  addition  four  complete  chapters  on 
The  Steam  Turbine  and  Mechanical  Stokers  which  is  not  included  in 
other  Engineering  Works. 

20th  Century  Hand  Book 


Engineers  and  Electricians 

A  COMPENDIUM 
J\_  of  useful  knowl- 
edge appertain- 
ing to  the  care  and 
management  of  Steam 
Engines,  Boilers  and 
Dynamos.  Thorough- 
ly practical  with  full 
instructions  in  regard 
to  making  evapora- 
tion tests  on  boilers. 
The  adjustment  of  the 
slide  valve,  corliss 
valves,  etc.,  fully  de- 
scribed andillustrated, 
together  with  the  ap- 
plication of  the  in- 
dicator and  diagram 
analysis.  The  subject 
of  hydraulics  for  en- 
g  1  n  e  e  r  s  is  made  a 
special  feature,  and  all  problems  are  solved  in  plain  figures,  thus  ena- 
bling the  man  of  limited  education  to  comprehend  their  meaning . 

By  C.  F.  SWINGLE,  M.E. 

Formerly  Chief  Engineer  of  the  Pullman  Car  Works.    Late  Chief  Engineer 
of  the  Illinois  Car  and  Equipment  Co.,  Chicago. 

ELECTRICAL   DIVISION 

The  electrical  part  of  this  valuable  volume  was  written  by  a  practical 
engineer  for  engineers,  and  is  a  clear  and  comprehensive  treatise  on  the 
principles,  construction  and  operation  of  Dynamos,  Motors,  Lamps, 
Storage  Batteries,  Indicators  and  Measuring  Instruments,  as  well  as  an 
explanation  of  the  principles  governing  the  generation  of  alternating  cur- 
rents, and  a  description  of  alternating  current  instruments  and  machin- 
ery. No  better  or  more  complete  electrical"  part  of  a  steam  engineer's 
book  was  ever  written  for  the  man  in  the  engine  room  of  an  electric 
lighting  plant. 

SWINGLE'S  20th  CENTURY  HAND  BOOK 
FOR.  ENGINEERS  AND  ELECTRICIANS 

Over  300  illustrations ;  handsomely  bound  in  full  leather  pocket 
book  style;  size  5x6%  x  1  inch  thick.      PRICE  NET  .... 


Sold  by  booksellers  generally  or  sent 
address  upon  receipt  of 


tpaid  to  any 


FREDERICK  J.  DRAKE  &  CO 


PUBLISHERS 


350-352  Wabash  Avenue,  CHICAGO,  ILL. 


Farm  Engines  and  How 


=THE 

ENGINEER'S  GUIDE 


BySTEPHENSON,  MAGGARD  A  CODY,  Expert  Engineer* 


Fully  Illustrated  with  about  75  beautiful 

woodcu'.3.    A  complete  Instructor 

for  the  operator  or  amateur. 

The  book  first  gives  a  simple 
description  of  every  part  of  a 
boiler  and  traction  or  simple  sta- 
tionary engine,  with  definitions 
of  all  the  technical  terms  com- 
monly used.  This  is  followed  by 
over  80  test  Questions  covering 
every  point  that  precedes.  Then 
come  simple  and  plain  directions 
to  the  young  engineer  as  to  how 
to  set  up  and  operate  his  engine 
and  boiler,  followed  by  questions 
and  answers  as  to  what  should  be 
done  in  every  conceivable  diffi- 
culty that  may  arise,  covering 
such  subjects  as  scale  in  the  boiler,  economical  firing,  sparks, 
pressure,  low  water  and  danger  of  explosions,  lining  and 
gearing  the  engine,  setting  the  valves,  oiling,  working  injector 
and  pump,  lacing  and  putting  on  belts,  etc.  There  are  two 
chapters  on  Farm  Engine  Economy,  giving  the  theory  of  the 
steam  engine,  especially  in  its  practical  applications  to  secur- 
ing economy  of  operation.  Chapter  XII,  describes  "Different 
Types  of  Engines,"  including  stationary,  compound,  Corliss 
and  high  speed  engines,  and  all  the  leading  makes  of  traction 
engines  with  an  illustration  of  each.  Also  chapter  on  gasoline 
engines  and  how  to  run  them,  and  another  on  how  to  run  a 
threshing  machine.  The  book  closes  with  a  variety  of  useful 
recipes  and  practical  suggestions  and  tables,  and  175  questions 
and  answers  often  given  in  examinations  for  engineer's  license. 
Beautifully  illustrated  with  plans,  etc. 

I2/1O  CLOTH.    PRICE  $1.00. 

Sent  prepaid  to  any  address  upon  receipt  of  price. 

Frederick  J.  Drake  &  Co.,  Publishers 


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HIM  13  '64  -A 

PM 

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LD  62A-50m-2,'64                              TT   .  Gen.eral  .L^ary 
(E3494S10  )  9412A                               UmverSgrgfegllforma 

